Hmm... okay, an earlier thread got me thinking about this. Am I the only one who finds the whole system of disciplines in Vampire, well, contrived? Seriously, legendary vampiric powers come in neat paths each containing five balanced powers? Entire clans only master three disciplines each? Somehow, I just don't buy it. Aside from really pointedly conceptual disciplines (like those of Sabbat clans and the ridiculous bloodlines), I'm inclined to think most of the major disciplines should be readily available to just about any vampire. And the ones that aren't would be a lot more interesting with quasireligious connotations rather than just nifty powers (Quietus and Serpentis especially).
Note that I don't include Thaumaturgy and Necromancy here. I personally would like to see them bearing even less resemblance to disciplines than they currently do. They're something else entirely in my book.
Anyway, next time I run a vamp game (God knows when that'll be, though), I think I'm going to experiment with making disciplines more flexible and less... well, less of a neatly organized system. Though I'll probably eliminate anything that isn't a reasonably traditional "vampiric" power.
(Oh, and as far as the other games go, Mage and Changeling are pretty much as flexible as I like and I don't care about the other games enough to worry about their systems.)