I really loved this story. At the beginning, I was rubbing my hands together and thinking, "Ooohhh... a Heaven Can Wait Snarry." But then you gave the story wings (pun sort of intended) and took it beyond the confines of the original.
The cloud-watching, the conversations in heaven, seeing them get closer -- all of those pieces were a wonderful way to set up the differences. Oh, and Snape and his 20 questions... just so brilliant.