Amir, Zeller, Olynyk, and Mickey are all backups.
I think it's best to stay the course, until we're ready to make another power move. Ultimately it would be nice to have Horford as our PF and another starting big. Cousins would be a great fit. So would Anthony Davis. It will take major assets to acquire such a star player, so I don't want to trade our chips for a slight upgrade over Amir. He's a good stop-gap until we invest in another major player.