Clanbase probably only caters for restrictive, professionally made stuff anyway (i.e. trusted companies that just make their game and not have any community decisions on game design shifting everything between patches). This wouldn't just only count out OpenArena but a ton of other games as well. Besides, OA has no anti-cheat, so that's a big nono for them, and my position on pro gaming has no effect on this, even if I did that oa486 thing (the low detailed pro cheaty high performance fork that doesn't exist) it probably wouldn't make it either.
This is mostly valid, although at least QL and NoGhost mod have quite a lot of community suggestions implemented. And they would pay attention to competitive features(cpma-alike), content and gameplay but not to dumbed down gfx.
Also consider size of community.
<3 ic.