I'll back up what has been said before regarding the gadgeteer.1. Damage is dependent on ammo, so find the best ammo you can. You can't damage if you can't hit, penetrate, and use the weapon, so modern weapon, dexterity, speed, senses.
2. The Omnigun is their best weapon. It's not just the damage, it's all those status ailments, tweaks, and add-ons that develop over time. Keep checking the gun after level-ups. Add in all that engineering brings to the game and you have a real asset.
Remember what has been said so often on these boards: Damage isn't everything, it's what the opponent can do to you. Veterans will often note that magic users are most potent when they buff the party and disable the enemy. The G-man can deal damage and disable at the same time with a simple stone.
Don't lose faith in the little nerd, check out www.geocities.com/jandrall/Wizardry8/SpotlightGadgeteer1.htm
for more. Credit to AtlusSeven7 and Jandrall for the info and the site.
As for me, nine parties to the CC and only one lacked a Gadgeteer. Although I did use a certain Trynnie for a bit!
Last night my nerdy little hobbit cracks off a round and blinds a sorceress in the cemetary dungeon after the party is nearly dead from a summoned elemental. Then he proceeds to insta-kill the elemental. My samurai will buy him lunch for the next week!