My Sorcerer class is a work-in-progress; the AoC campaign is playtesting it.
Last night it struck me that making characters save vs. corruption as a standard save vs. magic is rather more brutal than it is playable. Before they hit fourth level, almost any sorcerer is going to be irredeemably evil and showing physical signs of corruption because, let's face it, saving throws aren't easy to make in OD&D.
As a stop-gap this session I told the Stygian player that as a factor of the Stygian race I am extending his enhanced spellcasting to corruption saves as well...thus, he's always saving against corruption as though he was 3 levels higher than he is, this due to the fact that Stygians have a deeper innate understanding of and connection to magic than other races.
However, that's only a stop-gap. I need to come up with a way to give all sorcerers some sort of benefit when saving vs. magic. Perhaps make it wholly dependent upon the school of magic they use. Divination spells, for example, might be a straight save, while Prestidigitation saves are at +3, Nature magic at +2, summoning at -2 and Necromancy at -3...just off the top of my head.
More thought needs be put in about this. I like the idea of corruption saves. I like how they are working in practice. The slide is still a tad too quick for my liking.
A simpler solution would be to just spread it out one more time--make it 4 failed saves before you slide down a level of corruption instead of 3. Come to think of it, that might be my best option. It's certainly the simplest.