I really like the direction you are going for with this bow and that suggestion from 7thBattery sounds like it would lift the bow even more. I also like that it's huge, looks really epic.
Nannou, That custom animation will get a lot of attention. So put a gif in there to show it off. Modelers will like it for your insane use of the bones and people will like it for how unique it is.
Sorry to gush but... that looks AMAZING. I particularly like how the default animation has that bounce to it, which makes the mouth looks like it's snapping shut with so much force it rebounds.
I quite liked the white hair look too actually! Gonna have to play around with that before I finalise the submission. Here's what the completed brown hair version looks like.