Banrhart's been around a 89-90 wRC+ the last couple years. No slouch, but JT would still be a big upgrade if he's coming in around a 120-125 wRC+. If you think getting out of Marlins Park will help him out (a la Yelich) he could climb even higher. If they could get the deal done without Senzel included they could have a pretty interesting lineup next year with JT, Votto, Scooter, Peraza, Suarez, Winker, Senzel & Puig. Still no pitching to really speak of though. If the Marlins are willing to take guys that are a little farther out two of Taylor Trammell, Hunter Greene & Jonathan India would probably get them the bulk of the way there.