Brion-
A community deletion system with an automatically generated list linking to all deletion-nominated pages would seem to be the appropriate thing; this would eliminate the need to manually arrange a billion little debates; they could sit on the talk pages where they belonged, and the master list would manage itself.
Maybe, but you wild still have to solve the problem of showing all linked debates on the page. You can hardcode such a solution, but it will not be applicable to other cases, where things like refactoring are needed and you don't want a multitude of subpages (e.g. Village pump). I think the collapse feature is a good general solution that may well be complemented by other, more specific, functions later on.
Regards,
Erik