Until earlier this week, I was unaware that any such existed.
I never did quite finish Wiz8, although I played Wiz7 a couple of times, and all the Wizardries that came before them. However, while visiting the Wiz8 forum at Ironworks, I learned about mods for it hosted on the Flame Stryke site.
I played Flamestryke's mod, and I found it made the game too easy. VERY early in the game, you get a staff which regenerate your SP at a rate of +5...
Deathstryker's Mod is, as far as I know, very, very hard but dishes out lots of XP.
BTW, finish Wiz8, it's really a great game.
*