Hmm... neat story idea.

You know, imho, there aren't enough platformers out these days. Why don't you get a few artists together a persue this one?

I think the closest I have seen to have come to this sort of concept was 'Castlevania 3: Dracula's Curse' for the NES. (I guess I'd have to think back to my NES days for innovational concepts, after the SNES innovation has seemed to funnel.) Other than RPGs (and this is indeed like an RPG way of storytelling) I haven't really seen too much in the way of detailed story in many other genre, esp. platformers. Save for maybe a few GBA games, but most of those where RPG dual-genre anyhow.