If you have a Ranger, you'll want Wits on it anyways since Ranged Weapon combat ability increase critical chance and make Rage ability worthless for a ranger character.
Same goes for Savage Sortilege casters.
Also, use Burn my Eyes ability if you know you are going to go into a fight. It grants a massive amount of Wits that also scale on level making anyone with Burn my Eyes first on the turn. It can even make one of your character play twice in a row. If you have for example a Warrior who has 10 Wits and is playing in last, apply Burn my Eyes on him on the first round and He'll get to play last on the first round and first on the second round, effectively giving him 2 turns in a row.
The most common mistake people make is to put all point into Strength, Finesse or Intelligence. Wits, Constitution and Memory are also important.