I assume one is not entirely bound to one path? As such any wizard can cast Illusion?
Of course not! I would allow each wizard upon reaching 1st level to choose how many of the 4 spells he's supposed to get will be rolled randomly from the White Table and how many from the Dark Table. Maybe Elves, given that rp element of "good wise people" can only pick 1 Dark spell at 1st level.
Every next level, when they level up, they can pick again if the want to roll on the white or dark table.
I would love to see someone do this. The one problem I foresee is that it's not quite that simple. I imagine some domination-type charm spell that reduces you to a gibbering fool for the rest of your life is likely more to the Dark Path. Or perhaps divining through a giant eye above your tower, so that you can watch for and capture the Halfling with your ring, is not such a nice spell either.
Of course, spot on! The schools of magic where just a rough indication. Each spell should be classified individually, not just "every divination is good".
Example: Charme spell could be white (you're just making the target your friend); Dominate should be Dark (you're puppetteering the target); a "Know Weather" spell should be White, a "Read Mind spell" should be Dark Magic. Summoning should always be dark, unless your just "calling" a small animal to send a message.
I really think corruption chances should just be added to the spell charts and ignore "crits" of "fumbles" (that's what the chart is for already). Perhaps Enlarge has 0 chance for corruption but Giant Eye of Searching For Your Lost Possessions causes corruption on a 1-10.
Excellent. You mean like adding an entry at the beginning of the Spell table? In that case there could be some difference between easy/hard spells, and white/dark spells, which is reflected respectively in a higher base DC and a higher corruption chance:
EASY , WHITE SPELL
1 Fail, spell lost, Corruption;
2-11 Fail, Spell Lost;
EASY, DARK SPELL
1-5 Fail, spell lost, Corruption;
6-11 Fail, Spell Lost;
HARD, WHITE SPELL
1-5 Fail, spell lost, corruption;
6-15 fail spell lost;
HARD, DARK SPELL
1-9 Fail, spell lost, Corruption;
10-15 Fail, Spell Lost;
..... What do you think?!