Outfield looks set to me. Ludwick, Choo, Bruce, Heisey, Paul. Maybe add a depth guy who can play CF, but this unit looks set.
Infield is Votto, Phillips, Cozart, Frazier, Donald. One more guy needed. The only lefty bat is Joey, so I'd guess the last guy hits lefty. Maybe Hannahan. Maybe Burriss.
Catcher is set with Hanigan and Mes.
Starting pitching also seems set with main four plus new addition Chapman.
Bullpen seems more unsettled. Broxton, Marshall, Hoover, Lecure, Simon probably locks. Leaves two spots open. Arredondo? Leake? Cingrani? New guy?
So it's a utility infielder and possibly a new reliever. Possibly AAA depth guys. Anything more this off-season would seem to be a longshot.