I know you're working hard on improving it, and that it is a new mod, but I just wanted to point out that there seems to be a lot of floaty armor-ness going on. Not just with mods that also modify and put things on the player model (i.e. Mine & Blade, Wearmc), but armors from thaumcraft and tinkerer's consruct, as well. But I think they render armor differently from vanilla armor, so that might be it.
Also, for some reason, the attack animations do not work with diamond armor.