I don't play competitive melee games often, but when I do, I prefer Brawl Busters.
Now on Steam!
http://store.steampowered.com/app/109410During beta, I corralled about 6 RH to play at the same time. It was fun! Now there are new modes and more gear. It's not an MMO. It's a F2P online game, ala TF2, but mostly focused on melee! THWACK!