Hey, I'm currently the designer of Avatar World (based on Avatar the Last Airbender and other wuxia martial arts movies) so I'm one of the fellas doing a kung fu thing. And also don't worry about stepping on toes, there's always room for another design :3

Kung-fu as a whole can be done in a lot of ways, and the trouble with me for a lot of ideas is that the genre is so focused on combat and ApW is great for sweeping combat rather than repeated blow-by-blow stuff, in my estimation. Translating fights into a looser, more general set of rolls while still letting them feel like they last more than a couple rolls is a hard order.

Another big thing I'd recommend thinking about is the ebb-and-flow of things, from set-up (be it striking stances or charging up or whatever) to the follow-through of the actual action.

Stuff to think about. Interested in seeing what you get!