In my opinion, Hunters seem like the best in 6v6 gametypes and Warlocks seem the best in 3v3 gametypes. The less players there are the less likely you are to get multiple kills with your super, especially if the other team has a good headset and can easily determine where a super is being used. That's where grenades come in and Warlocks, in my opinion, have the best grenades.