Sing is most definitely the most underrated move in Puff's arsenal. I use that **** all the time because it lets you grab onto the ledge backwards. Especially on Battlefield, if I'm on a side plat I can run towards the ledge, shield-drop through the plat and fall past the ledge, then Sing to edgehog, because if you haven't used a midair jump you can "buffer" the Sing while falling without jumping. You can also just run or jump off the ledge and use it for instant edgehog. People have no clue.
Also, Rollout. It may be gimmicky, but its power doubles with each consecutive hit if you fully charge it every time, don't miss, and don't use any other moves in between (up to a maximum of 5 times, then its power resets). It also doubles again if you used Defense Curl first.