I've experimented a bit with heel flaps -- I have had the best success with the two edges looking the same, post-picking up stitches, with them looking how you describe. A nice chain like edge on one side, and more of a 'knotted' edge on the other side. In order to get the chain type edge on both edges, take a look at this link
. Personally, when I did it the way the link shows, I ended up with one side of my gusset having little holes all the way up.
Experiment though, and see what you end up liking best!