Try Nahlakh (1994) and Natuk (1999) by Tom Proudfoot.
8 characters to equip and different pre- and suffixes makes thousands of possible items to find, most of them random. Monsters also use items if generated with them.
I tried one of these (I forget which) many years ago, and found it interesting for a while, but I found that many of the tactical battles didn't actually require clever tactics. For example, I would get my band of 8 characters into a battle, where I spent time carefully positioning them and using abilities and spells... except it was just some easy enemies, that we could dispatch with little effort. Seemed like a lot of time spent for not much purpose. I also remember that the places I explored weren't that interesting, just some tunnels filled with some fights. Some fights were more challenging and therefore more interesting, but it seemed like it was mostly about getting into fights over and over (each of which takes a very long time) and collecting slightly better equipment.
That sounds like Natuk, which has it's fair share of "trash combat", where you may as well just turn on Quick Combat.
Having said that, I wasn't well versed in tactical RPGs at the time, and I may be partially confusing it with another game, Helherron, which had similar large party tactical battles. Maybe I should go back and try Tom Proudfoot's games again. Should I play them in order (Nahlakh and then Natuk)?
I always recommend playimg games in chronological order.
How different are they?
Are there interesting developments in the world / story as one gets farther in the game, or is it mostly just fighting?
The main differences are:
Nahlakh uses an improve skills by use system, while in Natuk you get XP which you use to improve stats and skills
Nahlahk has no random encounters whatsoever, no "trash combat" that I can recall, and in general has fewer but bigger and harder battles. No random encounter means that there are a couple of severe difficult spikes.
Natuk is more geared towards the OCD player and you can grind and build your character to your heart's desire if you want to. Also, it's less over the top than Nahlakh where you would fight armies of spiders, birdmen, dragons and aliens (I think they were supposed to be aliens). Natuk has a more traditional bestiary, and only one dragon (excluding some hatchlings).
Economy systems are different. In Nahlakh selling prices drop and buying prices increase globally for each game day, so the more time you spend going back to town to sell loot the less the profits.
In Natuk selling prices simply drop each time you sell an item. And being Orcs you don't buy stuff; you steal or loot it. Or buy if you can't role play orcs.
In both games you can never have enough money. You can spend gold on trainers to increase stats and skill, or on enchanters to enchant and recharge items.
There's really not much story in Nahlakh; Natuk is better in that regard. Natuk also has some Choices&Consequences. Killing people like store owners and tax collectors, will have consequences
Natuk also has one of the best endings of any CRPG.
Along with Disciples of Steel they have the best tactical combat of any CRPGs before (and probably after) Jagged Alliance 2 IMO. The magis system is also excellent.
But they are really not games for the "I play games for the story" crowd.