Played with a squad of 6 both with normal classes and some offclassing. Was still fun and some ranked up. Class limits are definitely needed.
Tried soloing after everyone got burned out and I pocketed 3-4 soldiers as med and they couldn't frag while we had one scout who was doing nothing but fragging and doubled my points while I was playing med. Some dude left part way through and all effort was lost. Not solo queuing anymore.
Edit: Got into games pretty fast, though for some reason my cfgs were working when playing with a group (I wasn't the group leader) and they were shut off when playing alone.