So, I cleaned up this walk cycle completely in Photoshop with the (gasp) pencil tool. I just made the size a little bigger than double, so when I re-sized it to the correct aspect ratio it anti-aliased. Worked much better than I had hoped, and I might end up doing this kind of clean up for everything else I animate. It was faster than flash, and was more forgiving than the brush tool.
My, my, isn't he Mr. Posture?