Hello,
I was just about to start a new Wizardry 8 run myself, although I was going to go all Hybrid.
It seems like Dexterity is the choice in the research I've done. The only time I saw a different choice is speed for the samurai and senses for the Ninja and Ranger. It seems like people look at the skills for each class and will choose the one that helps to raise the skill.

The answer is dexterity.

I have been thinking of starting a new Wizradry 8 run, especially since I reached an annoying floor in Wizardry: Llylgamyn Saga (Sega Saturn version) in the bonus dungeon; level 3 is filled entirely with one-way doors and single-screen rooms, at least as far as I have explored. (My party is level 11 or so, so no MALOR yet, though I did use Wizardry 1's Murphy's Ghost to get MADI on multiple characters.)

Anyway, my planned party has a mix: Figher/Valkyrie/Bard/Mage (replace with Gadgeteer)/Alchemist/Bishop. (The character replacement looks like it will come in Marten's Bluff or so, when I can get the second ingredient for the Holograph Projector, one of the best low level gadgets.) Interestingly enough, I am thinking of trying a party where everyone boosts speed, but of course I still have to boost a third stat at character creation, so perhaps DEX it will be (except for the casters, for which the third stat will be SEN, except for that Mage who won't raise INT).

It will be interesting going back to Wizardry 8 after spending so much time on the Japanese spin-offs; there are definitely differences (Dracon breath is really good in Japanese-made Wizardry, while Fairies don't make good Psionics, but Dwarves make good Monks).

Still need to decide on races for some of my characters, like Dracon or Mook for my Fighter.

Dexterity is the right choice. Check peddroelm's guide if You don't mind it being on steam - he unveiled quite a few formulas.

As far as weapons go it's apples and pears I feel. I'd go maces, but I've never played GS and it sure has its fanbase. There's a bunch of factors: Giant's Sword has extended range (as does the Vampire Chain), but uses a bunch of stamina due to its weight (which may be a major issue - not quite sure how decisive it is), has lower initiative and a bit more damage (14,5 DE & 19,5 tM vs 21 GS) as You probably know; also You'd get the items at different locations of course, which may define Your route through the game. You may find Yourself playing w/o either for quite a while, so the earlier swords / maces may matter. Guess the other "super-swords" don't interest You too much, do they? I seem to remember You are not going to pick up the *Light* *Sword*, even should You "luckily" find it, right?
In any case I'd consider the whole party: They may or may not want to take a specific route, might be able to replenish stamina, could take front or not to make extended range more or less worthwhile. Ultimately both is fine I guess.

*Shoulda checked the date before... Anyway - perhaps You can still find use for a late answer :p
The gog forums aren't as active as they used to be anymore, are they? Kind of sad :(

(It's been a while since I last posted in the thread, and I've moved on to other games.)

With respect to availability, I should point out that, if you can reach the Diamond Eyes, you can also reach one of the enemies that drops the Giant's Sword, as that enemy drops the Diamond Eyes.

(By the way, in the Wizardry Gaiden series (Wizardry Gaiden 4 and Wizardry DIMGUIL, in this case), the Diamond Eyes exists, it can be used in the off hand, but it doesn't look like it's that good.)

its good for Vi to build her mace skill up with

Wizardry Gaiden is one of the RJPG titles, is it? Say how do the "western" and the japanese titles relate to each others? Were those made by SirTech too (the older ones anyway)?

Valks get a polearm bonus, the most likely(99.98%;) best vanilla weapon for Vi is the Dread Spear.

To get rid of the mace, have a character with an empty slot in personal inventory,
along with an item stack of at least 2 instances.
Take the mace, drop it with r-click on the other characters portrait,
then left click that characters portrait to access its inventory,
hold shift to pick up a single instance from the stack,
l-click Vi's portrait and give it to her, she will have forgotten the mace. (shift+click is the crucial part)
You will have to repeat the procedure if she ever gets her hand on a stun mace again

I guess she only has the mace flagged because her animation uses a mace. I could change that :)

btw Vi Domina, the missing sound file when she learns a spell etc and moves her lips but does not speak

www.mediafire.com/file/6rt3by9h8kbryv7/Missing_SoundFile_for_RPC_Vi_Domina.7z/file

It's one of the Japanese Wizardry titles, or rather a series of them. (Note that I count Wizardry DIMGUIL as being in this series, as it has the same developer and similar gameplay elements to Wizardry Gaiden 4.) The Wizardry Gaiden series was made by ASCII, who was also responsible for early console Wizardry ports (including 3 that did make it to the US, one of which is a rather interesting arrangement of the Knight of Diamonds scenario), and was also involved in creating the MSX standard. ASCII also ported the games to many Japanese computer systems, including the MSX and FM-Towns.

As for how they relate to the Sir-Tech Wizardries, Wizardry Gaiden 3 and later add classes and races from Wizardry 6, and there are some references to Wizardry 1 and 2, but otherwise there isn't much relevant. In fact, there is an interesting inconsistency between Wizardry Gaiden 3+ and Wizardry 8:
* In Wizardry Gaiden 3 and later, Valkyries can only be Neutral.
* The Dark Savant can be considered Evil, as that seems to be the intent of the developers of Wizardry 6-8.
* Wizardry 8 makes it clear that Vi Domina does not like the Dark Savant, and would not willingly travel with him. This means that her alignment must be opposite of the Dark Savant, which makes Vi Domina Good, and hence ineligible to become a Valkyire. (Also note that characters can't change between Neutral and other alignments, at least not without IHALON (Wizardry Gaiden 4 of Wizardry DIMGUIL version) being cast on them with maxed out stats.)
* Wizardry 8 makes it clear that Vi Domina is a Valkyrie; you can recruit her into your party, and if you check her stats, she is clearly a Valkryie. If you're going pole-arms, there's also:
* Lance, which has an instant kill chance and can be bought right there in Arnika. (Why can't plain Fighters equip that particular weapon, anyway?)
* Stun Rod, which can paralyze, which is quite helpful, and is again buyable from Sadok.

Both are good enough to be used as long-term weapons, and both are buyable (without going into Rapax territory).

In wiz8 the default number of attacks and swings in a single turn
is based on the characters (snake-)speed, dexterity, combat&weapon skill, and lvl
the weapons weight will shift the required values for above modifiers at thresholds 6, 12 18 ... lbs,
the latter perhaps slightly modified by the characters str (not sure about the latter!)
Additionally the characters stamina level effects the final result.
The dread spear weigs 6 lbs, lance and stun rod 18 lbs,
so require much higher skills and attributes to get the same number of sings/turn.
The higher weight will drain stamina faster
which either forces you to focus on str to at least partially compensate,
so dex & spd rise slower which affects attacks/swings/turn,
or to cast a decent Rest All each turn (unless all others lose only little stamina)

The kill chance of the Lance is pretty nice but not supported by class skills,
i.e. will never rise about 4% base chance (modified by target lvl!)
The stun rod gives 10 polearm bonus and the 20% paralyze are imo better than 4% kill,
as it also works and every monster and is nearly as good as dead.
The spears hex only puts a big dent in peformance but 50% have a good chance to work,
the +20 polarm will ensure that she gets 3 attacks with 3 swings each much earlier,
if you can get that at all with a 18 lbs weapon,
as its eats enough stamina during the turn to limit performance for the last attacks.
(perhaps if a fast medium and slow stamina caster support her;)

The dread spear has the highest min and avg dmg of all 3,
so its certainly better vs high lvl targets who tend to resist the side effects.
It is also sold by Bela, pretty easy to reach by luring the golem away from the bridge.
If the mountain path is clear :)
And while you are there, kite the one in the lake away from the waterfall (done on avg lvl 3-4 ;)

Place Vi solo in the front quadrant, step into a doorway in Arnika/etc with monsters near and save,
then compare dmg+turnsToKill together with required support in several tries to get a practical performance output for each item.

Vi is a special case and she uses a mace

[spoiler]
even if you build her to a different weapon she will always drop them and use her mace in the final battle so your best option is to build her mace skill up

(Endgame spoilers in this post)

But does her mace skill actually carry into that battle? My understanding is that she leaves your party and becomes an NPC at that point, at which point her stats as an RPC are irrelevant.

(Also, still wondering what happens if Vi is in your party but dead once you reach this point, and in particular what happens if you're going for the evil ending and revive her during the Bela fight.)

A Wiz8 RPC which is released from party transforms into the monster to which the NPC/RPC is assigned.
Character improvements, class changes, equipped items etc are not taken into account at all for that monster,
the game is not even designed to be able to do that.

Vi is a special case in this regard because the Vi monster that appears at the cosmic circle
is different to the Vi monster that appears when she is deliberately dismissed from party.
( [Vi Domina# 5 Arnika] aka monster ID#395 and [Vi Domina#8 CC] aka monster ID#441] )
The devs probably did this to prevent the exploit that you can dismiss a RPC before combat
to have the stronger monster outside party on your side instead of the weaker RPC with you.
The standard Vi has lvl 5, the CC Vi lvl 17, despite the "# 8" in her name.
the [#] was most likely used by the devs to instantly see a monsters lvl by just looking at the name
without checking its actual data set (the game suppresses the [#] and all following characters in a name)

btw you can also have 2 RPCs in party and a 3rd placed where you need it,
either RFS who stays where he was dismissed,
or you move 3 RPCs by dismissing RPC1, move into the desired direction without losing line of sight,
dismiss RPC2, move back to hire 1 and move beyond 2, dismiss 1 to fetch 2, and so on.

In the early game the released RPC respectively its monster it more effective than the RPC in party,
but that advantage soon vanishes with lvl and skill increase.

The text strings for wiz8 monster attacks like "bashes mace", "swings sword", "kicks" etc are for decoration only,
it does not change any of the attacks other parameters,
same for "weapon matter" which only affects the hit sound according to target material.

Is it possible for both Vi monsters to exist at the same time? If so, could it be arranged so that the Vis are fighting each other?

Yes, you can even have multiple instances of the same Vi monster present in the same location,
but if you speak to Vi#1 and hire her, let her die and remove the corpse from party,
the NPC is registered as dead aka dead_beyond_revival aka removed from database(FACT ID#534, named "Vi_is_dead]")
and the remaining Vi monsters will lose the NPC option, i.e. it will not speak to the party and you can not hire it/her.

You can trigger the battle between the two different and even 2 identical Vi monsters
if at least one of the instances has a "friendly" attitude assigned to party
(the attitude is adjustable individually for each instance, respectively template for spawn generators,
not only global(or should i say "discal"? ;) for all monsters of a specific ID#

Note that the Vi monsters will not fight vs each other by default,
as usual only if the party is near and triggers a battle within their view.
(during tests with Zant + trang and Yamir & Umpani in same location
I noticed at some point that the 2 factions fought each other,
but I am not sure whether i triggered the hostilities with actions of my party.

To let 2 Vis fight each other "automatically" run Cosmic Forge -> Monster Editor,
select e.g. monster Guardian Golem ID#49 and hit "Recreate From ...",
select Vi Domina ID# 395 as template to watch a fair battle, or the CC Vi ID#441,
save changes in monster editor and CF main menu.

Now in game go to the Arnika Bank basement and release Vi in front of the door.
behind which the golem spawns, open and step slightly back,
so that the released Vi stands between party and Golem_Vi

You could also replace all instances of elementals (ID#25 - 48) with instances of VI,
with the option to either keep the elementals properties by only assigning the model script of Vi,
(some adjustments may be required to prevent crash caused by expected value(s) not present at all;)
or use the "recreate from.." option for a 100% clone.
Now an Instance of Vi will appear whenever you cast summon elemental