I see a lot of the newer players worrying about unlocks when there's really no need to. Vehicles would be a problem, aircarft in particular, but infantry combat is a fairly even playing field where some of the better weapons unlock really early.
I think the important thing is picking something and sticking to it, its too tempting early on to flit between different classes and weapon setups and not really get anywhere. For instance going support and getting 11,000 points nets you C4 and a M249, those points can be gotten in a couple of rounds. The C4 takes care of armour and after 60 kills with the M249 you unlock extended mag, holo and foregrip - thats a ready made killing machine in under 2 hours of play time.