Hey guys, I'm going to boot up this game and again and I want to go through as someone who mainly uses firearms and is heavily tech-based.

Anyone have any hints/tips or suggestions for character builds to go with? I heard it is a lot harder at first with firearms! Any help would be appreciated.

I haven't tried firearms myself but the usual advice is to take at least one point in melee for when you run out of bullets. Also, in the very beginning your guns will be weak so you want to be able to hit things that get too close.

You should also learn to make your own bullets. This requires either one point in Explosives or a tech manual for Explosives, and that you find / buy the schematic for bullets. Making bullets yourself means you'll run out a lot less often.

As for stats, you want Dexterity mainly and some Perception. Strength always helps for carrying more stuff, but won't affect gun damage. Intelligence to learn tech disciplines. For skills, you want firearms (obviously), and you can take gunsmithing if you want to build your own guns rather than just buy them. Alternatively consider other disciplines like mechanical to make robot allies, herbology to make healing items (although you can get a follower who can make those for you) or anything else that sounds interesting.

Gunslingers are allegedly a bit tough to play, so if you are worried about difficulty you might try a grenadier instead. Focus on the explosives disciipline and throwing skill, use a boomerang for backup, and build lots of grenades out of trash. Grenades never hurt you or your allies so you can throw them at enemies even if the enemies are right next to you (although I thought that was kind of silly). Add a second tech discipline for variety.

Game balance has always been an issue in Arcanum. You'll run into that with Gunsmithing internally.

1) Intelligence is going to be a major stat for you, topping at 19 if you want to run any discipline to its conclusion. Therefore you'll want to consider picking skills which are dependent on Intelligence. There aren't many, and not all are universally useful, but it's definitely worth considering. To my knowledge, this is only Heal, Repair and Gambling.
I enjoyed playing a gambler, but it's simply not necessary for anything, and nobody will gamble with you after you win a few times against them. (One possible exception, and even he puts up a fuss.) Repair becomes somewhat useful when you train it to the max, and Heal becomes more useful to a technologist than to a mage.

2) A very high intelligence is prerequisite for certain dialogue options, but so too is a high Persuasion (and therefore high Charisma.) If you wish to take advantage of some of these dialogue options, you'll need to build a character capable of reaching those plateaus, perhaps even topping out Persuasion. Alternatively, if you wish for a less diplomatic game, you might consider Charisma something of a 'dump stat' just to help you resist the temptation.

3) While you can't go wrong with a touch of melee, I can tell you that, with a competent party, I took a physically weak technologist clear through the end of the game without a single dot in Explosives or Melee. It helped that I knew where I was going and what I was doing, but nevertheless it's quite possible. I even got my pick of the endings if I so chose.

4) I think the comma key ( , ) might be for headshots. Can't recall for certain. I know I used it a lot with her.

5) The Hand Cannon is an excellent gun even in the late game and the guns immediately following it simply don't surpass it. If you wish to run gunsmithing to its most impressive conclusion, be prepared for a few disappointing guns before you get to the bigger buggers at the end.

6) None of your followers will every be truly good at anything. Not really. If you want something of good quality or high level, you have to do it yourself. Combat, maybe, you can foist off on others. (Especially the dog. Look up the dog. You may or may not wish to worry about him as a party member, as he's a bit of an experience hog, but you only get one chance to save his life.)

7) Try not to worry too much. Do what's fun. My advice here is to help you pick the things which allow you to have fun with the least pain or difficulty.