Regardless of my position on the armor it is highly unlikely that Hayabusa will make a return to the Halo franchise. The only reason it was included in Halo 3 in the first place is because Dead or Alive 4 was in development. Team Ninja and Microsoft wanted some sort of partnership Team Ninja got a Spartan and Ms got Ryu Hayabusa's armor. Though Team Ninja did want John-117 instead of Nicole, but you don't always get what you want so they settled.
All that said I feel that the Helioskrill armor is a great replacement for that "ninja" feel. I personally disliked how the armor was handled in Halo 3, but that is neither here nor there.