If Jordan Mickey is smart he'll watch a lot of tape of Perk in a hurry. He's nowhere near as imposing but knocking some guys around a bit will probably buy some minutes and hopefully become contagious. Haven't seen enough of him to say if that's in his personality or not, though. He just seems like a guy that could grab a role right now.
I think a lot of this will take care of itself once Crowder and Horford get back, though. Even Olynyk is a bit physical and had stretches of excellence on D, especially helping, last year.