When the Jays acquired him the scouting reports I read were that he was a passable CF and a good corner OF. Turns out he's a bad LF which really tanks his value a lot. He was also supposed to be a stolen base threat. He's been clocked as our fastest player but his minor league steals aren't translating to MLB.
That said, even though he's 25 he barely just passed 500 big league ABs so he could still make some adjustments and improve with the bat, his glove and even his base running. I think at this point the floor is a platoon LF (perhaps with McKinney making up the other half?) and the ceiling is a 3 WAR player if he can make some improvements.