Replacing Old Ben with Chopper as a Rebel Tank

Usually you don't want chopper as a tank. He has a one turn taunt and he is fast so that one turn is over very quickly. What's more there is a three turn colldown. I suppose you can speed the cool down slightly by using ezras watch and learn (chopper is a support) to charge meter a little.

Also if you are facing buff heavy teams chopper can cleanse them off (recharging protection and draining turn meter). The 10% turn meter reduction on all enemies per buff on the targeted enemy can really buy some time.

In balance I expect it to be a bad idea but you can play with it if you like. I think it's more likely to work with bb8 r2d2 rjt team.