I like 6v6 because it makes luck a much less significant factor. A critical in 3v3 can be impossible to recover from. Also, 6v6 gives more overall coverage to common threats and takes away the rock-paper-scissors element.
Just make raqequits normal wins/losses for both players. Seriously
"Not everything is a lesson. Sometimes you just fail." - Dwight Schrute "I don't get high, life keeps me at a decent height." -Lupe Fiasco