Thing about Jozy out wide (and I guess Cooper too, though he also lacks the acceleration that I think would have been a deal-breaker for him as a wide player) is that he doesn't have the best set of lungs in the world. That big frame of his wasn't made for a lot of long runs. Hearing about him getting gassed in that sort of position is nothing new. A 4-3-3 is different from a 4-4-2 in that regard--if I knew we for some reason had to play a 4-4-2, and that Jozy had to start, I'm starting him at forward. In the 4-3-3 that might well not be true, but then it opens up a whole case of questions about what other players would fit into it.
Yeah at this point his game is made for playing off a target or playing in midfield. I proposed sometime ago that he make a transition to midfield in the manner of a Dwayne DeRosario at Houston--though perhaps in 4-5-1 instead of 4-4-2. But the lungs needed to cover ground is the big limiting factor. It's an open question as to how much Jozy's stamina can or will improve. Perhaps he needs to drop down a few more levels of league and continue to improve his game as a striker? Not saying he can't improve the stamina enough to be effective over 90 min...