New player here, advice appreciated

Agree with Koryphaia. You're so close, just unlock Ackbar. Then go get St Han. Wedge has a great leader, but Ackbar is really good too, especially when paired with St Han. When StH taunts, Ackbar lead calls an assist from another Rebel ally, so you don't lose an attack. Plus, Ackbar's Tactical Genius allows a hero to go twice in a row, so you could get a Wedge AOE followed up immediately by his basic, to potentially devastating effect. Even more effective when Lando uses TG. So don't feel like AA is a complete waste; he's very useful.