Eno's a Brit. And Reich's been remixed (the "Reich Remixed" CD) by electronica artists. Partch seems too idiosyncratic to be labeled classical. He's certainly not part of any performance canon.
> What differentiates classical from pop in Indian
> is discipline, ambition, and context.
No formal elements? And success in both Indian classical and pop musics require ambition and discipline (from what I've seen as a not very knowledgeable fan of some of it).
Uday