Personally I've had a lot of fun in beta 1, despite not being in a clan. I've found that it is entirely possible to rambo, it is just harder when the other team is actually working together. Medics and technicians can really rambo it up if played right. They are my class of choice for taking/retaking capturable spawns, nothing beats their survivability.
I really think all the nay sayers are over emphasizing the "clan" quality of this game. The pub servers will still be loads of fun. Pub servers are nice because one or a few exceptional players can really influence the flow of the game (as opposed to a clan game where everyone is exceptional).