I don't think making segregated lobbies by level will be good for the community as a whole. As it stands low level players tend to quit out of high level games out of frustration or fear.
I think it would be a good idea, for the reason you just gave. People ragequitting is a problem for people on both teams... And often it's because of:
As you said the high level players tend congregate on ones side causing rofel stomps.
That. It's not much fun for either side when games are so obviously mismatched. I really don't see why the higher level captains do this. Often they'll even see several people join on the other team in the lobby and quit straight away. Making more "approachable" games would mean they'd start quicker. I don't like playing in such games (on either side). Why not just move your whole ship across to balance things out? You may not be playing
with your friends/clanmates, but by playing
against them you'll actually have a challenge, rather than just obliterating the lower level ships yet again. And who knows, by each teaming with a lower level captain, you might even find new recruits for your clans.
Captain level mainly; a low level crew with a high level captain can hold their own against a higher level crew, but a higher level crew with a low level captain don't have much hope.
Yes, I know level and ability aren't directly linked, but there is generally a correlation...One thing I suggested in another thread was a number displayed, for each game in the list, showing the average captain level. That way potential joiners (both high and low level) would have an idea of what to expect.