Genosian Soldier and Luminara but no Lando? Looks like you've followed some outdated guide/advice.
I would recommend getting a squad of 4* scoundrels for credit heist ASAP. You will need the increased rewards for doing the highest tier compared to lower tiers. Credits is an important ressource. Lando and ST Han Boba are particularly usefull for that. Lando due to his skills that come handy in lots of game modes. ST Han because he's also required to get Commander Luke Skywalker. And then they are both rebels.
If you promote more empire toons from 4* to 5* you will be ready to unlock R2D2 next time his event comes around. (Will probably take some time as it was just there).
For the time being, jedi are probably your best bet in the arena. However, you lack attackers. Bariss and QGJ are good in the arena. Ezra and Kanan could make great additions. Ezra for his strong damage and Kanan for tanking. Both are rebels and Phoenix and hence useful in other game modes as well. Until you get then ready for arena, you could maybe use Rey and Boba together with QGJ lead, Mace Windu and Luminars. No, there's not much synergy (yet) but I believe they will do better. JC is more or less cannon fodder, and Barris doesn't shine until you get a zeta on her unique.
You really should move your best mods to you current arena team. Your best speed secondaries are better used on your arena team. In general you could really use some better mods. With increased credits income, you will have enough to buy a good mod now and then from mod shipments.