C-3PO + CLS Phase 4 Traya

So two things occur to me when replacing Han: That's replacing multiple resists per turn, and also replacing his damage. In p4 it's not a potentially infinite loop, as she will always gain tm from Furious Foe. So the team has a finite number of turns, so high damage counts. Leia could work, but on the other hand, replacing Han's double shot with multiple debuffs on a single hit sounds ideal. Cassian I think could work, but he seems to have naturally high potency. I don't know how hard Bistan hits on his basic, but he does seem like a good choice. Although if the idea is saving Han for p3, keep in mind you're either using him on a 3PO team which kills this, or Chex Mix, which uses CLS. So you don't NEED to replace Han. If you're doing something else for p3 (Bounty and the Beast, etc.) then you'll have Han available.

For replacing BB-8, I like the Chopper idea on paper. Things could get messed up if 3PO gets the speed up and goes too early. But like BB-8, he doesn't need three stacks to reduce cooldowns, and even if he reduces Ezra's, that might give you a chance to have him call 3PO again. The assists to Ezra and 3PO mean more chances to reduce, as well as get resists.