Decades could work, of course if you go earlier than the 70s or 60s, half of CHUD will be watching from the sidelines. If there's a willing enough contingent of people interested though, you could certainly do it. I mean, it's not like we're never going to do more than one draft in the future either, so it's entirely plausible and people will enter the ones they know.
Genres could be accessible too. Comedy could be everything from Ernst Lubitsch, to the Marx boys, Tati, Anders Jensen, even the new stuff like Apatow, Edgar Wright, and Shane Black. Hell, there go my draft picks. Strictly foreign might be doable too.
But Criterion's a good call. An Oscar one maybe, just any category winner, but that get's confining and involves a lot of "Wait - what'd that win?"
I think we can all agree Kirby knocked that last one out of the park though. I wasn't in it (it's finals week) but I read the discussions and thought it was handled pretty well.