If you don't play on tournaments, you can cobble together some "counts as" figures for almost everyone of the specialists. I dont believe they will truly shine until vehicles come out.
Ive done well with snipers and even made my 3rd set from some extra commando/trooper figures and small plastic rods. Wookiees dont fit a great rebel theme yet. I have 2 units of fleets but that's because my opponents are afraid of them for aome reason. Ewebs I'm not impressed with. Fd1.4 turret is average but a different playstyle than most other units.
Deployment is everything