Thanks for your tip with anatomy studies, but I am doing at least each day one and I think the anatomy is Ok
(if not feel free to point out the places where the "anatomy" is off). There wasn't any desire to keep the proportions photorealistic and it wouldn't even make sense since it's a game graphic with pixels and they will be also animated later. Too much danger to fall in the "realistic gap" which would lead to a hell of work for nothing, because the pixels are too rough for this.
THe most important thing is to communicate the charakters personality. I think it's necessary for the style with the big heads, to counteract this with the shoulders and arms. I don't think it's really convincing to make the faces smaller because at 100% they are atm really small. I also think that changing the body proportions to a chibi style will destroy the more earnest style.
Unifiying the body shapes won't be a good idea too, because atm it's clear visible which char is male and which female. And since they are drawn in more or less 3/4 RPG perspective (I also took some liberalities with this to make their reading better) there is not much I can do with the head and the shoulders and this place looks still a bit off to me, but I don't know how to do anything about it right now.
If you want to discuss the style, or you can bring up some convincing examples or ideas feel free to share. If you just dislike the style, it's hard to discuss this topic.
Hue-Shifting is also a matter of style, I think reducing it would seriously harm the magic feeling and lead from the more naturalistic style to a realistic direction.
If you have something constructive to add I'll definitely listen.