OK, thank you all for your advices, indeed I’ll try to see tomorrow if I can make the edges of the effect a bit smoother. Here’s an improved version of part 2 :
And here’s a first draft for part 3 :
pw : fanedit
Looking good, like I said size and shape and all that looks spot on. But yes if you could work on smoothing it then it’d be perfect, you can still see some of that crunch in the close up shots (not as much an issue when further away or in fast motion - finding the right balance shot to shot will be key).