Being a big fan of Glen Cook - who was influenced in turn by his friend Fritz Leiber - I like my wizards weird. Not powerful, wise old men full of humor and stories with glinty eyes and pipes.
No, I want bug-***k crazies who have warped themselves in the pursuit of power. The Limper. Varthlokkur. Soulcatcher. Sheelba. The Egg of God. The more power you seized, the more the cost you paid.
In all of my games since I discovered Cook's books - especially the early Dread Empire books - I have had odd wizards.
Felltower has a much smaller selection, but they're still odd.
Black Jans, wizard of the disappearing tower, possessor of many titles and the end market for cursed items the PCs sell.
Old Witch of Molotov, Black Jans's rival. Little is known of her except that her house moves with her.
Lassirev the Enchanter, experimenter on the crystal mirrors and possibly possessed of the knowledge of the black library.
and a few the PCs haven't run into yet.
The PCs are equally odd:
Dryst of the large helmet, heavy armor, and refusal to walk, who treats his Created Servants identically to how he treats the PCs - as disposable resources of varying value.
Nakar the Unseen, who spent his life (and then his death) Invisible.
The Barca family, a collection of single-element obsessed wizards, all of whom jealously hate each other but who worship the family name.
Gerry, the clueless necromancer who brings his skeletons to church with him.
Frankly, guys like Desmond, who only throws Acid Ball spells at women and children, or Volos, were pretty normal by game standards.
And DF and the DFRPG, sprung from GURPS, allows a very wide variety of weirdness for wizards.
It's become a thing for the PCs, as well. All for the better.