I recently played a 6th level fighter, 20 point buy, who I dumped a 15 in his Charisma and spent a feat on "Skill Focus - Diplomacy." He spent some of his wealth on a hat of disguise and had ranks in the disguise skill.
I marginalized the hell out of the wizard. He took his turn when I got around to letting him, if I didn't handle the situation out of combat or 1v1 the enemy ahead of time while they weren't ready.
In group fights, I still did just as good as an ordinary fighter because fighters are way over qualified in pathfinder for CR+4 encounters if they can get into combat. Archery got me into combat all the time.
I'm sure I could fail will saves 7 times out of 20 instead of 5 times out of 20 like and ordinary fighter. I'm not going to loose much sleep over it.
A year or two ago I had a fighter that was marginalizing casters. He had a cloak of dimension door, step up and combat reflexes. He'd appear next to the enemy, carve them up, and full attack finish them the next round. The party wizard is still casting his full round spell or summoning something when I direct him to what he needs to do, usually cleaning up my light work.