He's raking LHP this year but doesn't usually (albeit, better than Marsh, which is a low bar, and good enough for a top defensive CF). Used to switch-hit but couldn't hit LHP at all when he did that.
I still don't think you keep both Marsh and Kepler if you get him, so you'd almost have to punt on Kepler because Marsh still could have a role on this team for two more years. Unless you really are ready to sit down Nick quite a bit, then the three of them could share both corners. But do you keep Rojas if Mullins is an everyday player?
I'm afraid Bautista alone might cost you Abel, or at least an Estevez-like package. To get Mullins too might take three prospects.