Since his rookie season, Steen had pretty much stopped developing any more as an offensive player. Defensively, he has been good, but Toronto has a few forwards who can play both ends of the ice effectively. Carlo has been too injury prone. He has shown some instances of his great talent, but those instances have all been far too brief to have an impact on this team.
Since I haven't seen a lot of Stempniak in the past few years, I don't have a lot to say a lot about him. He did score 27 goals in 2006/07 and looks like he will be a more productive player then Steen, and he is only 25 years old.