Well, on the heads, as I was comparing it to the original sprite, It looks like you have reversed the shading(the light parts you changed to dark and vice versa). I think you need to shade it more like the gen you were trying to revamp it to and it will be fine.
when doing revamps, you have to completely reshade the pokemon. What you did is a recolor. you should reshade it, update the outline, even change the shape if neccesary.
Try reading a tutorial, it will show you what I mean.
