Who is a good "tank" for R2?

So, my r2 is about ready to move into my arena squad. I currently run Rex, boba, Palp, tie pilot, shore. Once r2 comes in, who should he replace, and who would the be the ideal candidate for his smoke screen? (No chaze or Kenobi for me, and I don't even have Kylo unlocked). Based off his ai, who would he Target with it that would work well. Fives seems decent, but no one uses him so there is probably a better choice. I'm about to drop 20 zeta on R2, so my Savage won't be in the proper shape. Suggestions?
This is what I have to work with:

https://swgoh.gg/u/heroofcanton/