Yes, exactly. This is the "Can I..." problem? "I don't know, can you?" Or the classic Matt Mercer response, "You can sure try." I take a few seconds at the beginning of each session to remind my players that intent is all that matters. What is your intent? What are you looking for? What are you...
Just remember that you designate the ability when the spell is cast, you can't switch the ability that is hexed from target to target. You'd have to recast hex to switch from, say, STR to DEX.
This should have been a short argument, as Charisma is not a measure of a character's beauty. Hitler had a high charisma, and he was uglier than a sack of smashed @$$holes.
First advice. Tell the players "No" and reboot your campaign at level 1.
If they threaten to mutiny, then it's time to pull out all stops. I recommend Demons or Devils (a trip to the Abyss should help them find perspective again). If there's no plausible way to end up in Hell or the Abyss, then...
Howdy! I'm new myself here...
Just remember, Einstein was a pacifist, and he personally endorsed the development of the atomic bomb... Something to think about when developing a "pacifist" character.
I want to echo what others here have said. You're pretty much screaming "C&C" with your 3.5 woes, which I assure you Pathfinder won't fix. Having both systems on hand, C&C addresses what is probably your biggest concern - prep time. I can write volumes about my love for C&C, but I'll spare you...