Tips and tricks.
Well, as much as I can give at this level.
If Bernd tries it, one thing I can suggest for sure: it's better to kill the enemy faster then slowing them down to kill your party. So prioritize offensive feats and skills over defensive.
This also means try to be first in combat, high initiative is great, you shoot first, so you might be able to take out one enemy right in the first turn even before he would fire a shot.
This also means take First Draw feat ASAP. Besides the Initiative it also gives AP!
And then it might be better to have high Evasion skill than high Armor, better to dodge and got no damage than get hit and get some.
It matters who scores the killing shot. Also if you score critical, your Critical Strike skill goes up and with that the critical chance too. Perhaps on killing the enemy, even if with normal strike, it might add to critical. Have to check the messages in the textbox.
Also when it comes to Faythe's quest, after the fight she'll ask something. Depending on your reply she'll get a feat, either Assassin or Thief. The first makes her better suited to fight, while the latter allows her to be a skill monkey. Have to take care because with the second route she can "die" in the fights all the time (unless high evasion).
Oh, something else, when you choose difficulty at the start of a new game, Underdog can really teach you how to conduct a fight. You might get stuck at one point because you pick feats stupidly or for bad stat distribution or whatnot tho.