I didn't really pay attention to the Lebron returning to Cleveland talk until now. If the Heat lose there's a very good chance Lebron will return to Cleveland to save face and to save his legacy.
This puts the Cavs in an odd position because James is so fickle. The Cavs will build preparing for Lebron James and his return and he might not return. So the Cavs will be in Lebron limbo if the Heat lose. If they lose Lebron will go back to being Lechoke and Lebum because he couldn't win a Championship with Allen, Bosh and Wade.
I will say this, if Lebron returns to Cleveland the Cavs could become a dynasty. In this scenario Nerlens Noel would be the best pick if his knee checks out. I don't want to pick Noel but if Lebron returns it might be a perfect fit.
The main thing you would need is more wing players.
With Irving, Waiters and James at the 1, 2 and 3 you want some Danny Greens on the wing. Maybe look for a stretch 4 that can shoot and pick up players like Dorell Wright. We will hopefully have Ellington as well.
So it all comes down to if the Heat win or lose this Championship series. If they lose there's a 60 to 70% chance Lebron returns to Cleveland. It may be even higher than that. If the Heat win the series, Lebron isn't coming back to Cleveland. Back to back titles will clear up all the pressure on Lebron and he will not return to a pressure situation in Cleveland.
So if the Heat lose pick Noel if his knee checks out and prepare for Lebron.
If the Heat win, pick Porter and start building now with securing the wing.