He's already beaten Bader and Davis in Bellator, I would assume they give him Corey Anderson next, but after that I dunno what's left for him in Bellator. I don't think Polizzi is ready yet and I don't think potential matchups with old Machida or Anglickas are very interesting really.
Maybe Moose could move to LHW, I'd be interested in that fight. I suppose he could also avenge the Albrektsson defeat from years ago, but Karl needs to get some wins first.
But in the UFC I'd love to see him against any of Reyes, Santos, Blachowicz, Ankalaev, Rakic, Prochazka, Volkan, Rumble or Glover.