This one got character and coloring is nicely done.
Moderation for:
BTNChaosGeneral The color value is true to the in-game icons style. One of your better works. I liked the shapes.
BTNKargathBladefist I'd move cheeks higher and reduce the red. Highlights could be stronger on cheeks as well.
BTNFacelessOneCultist Not quite significantly edited, but there was some work and icon looks fitting to model.
BTNGunSlinger Showing move of his hair and moving him more to right may would have been beneficial for balance of icon. He is leaning towards upper edges leaving a lot of space on the right. Problem in balance comes when left and right space come into interaction, one is dominating drawing unnecessary attention. However it looks good and colors are fitting for in-game.
BTNHyppoPriestess From the process gif you posted, moving her lower face upwards was not needed. This is an uneasy perspective to work with and you need shadows to help you in positioning, especially in icon size. So, more contrast maybe would be helpful.
BTNSylvan Enchantress Overall looks fitting for in-game, however the original perspective was altered to front view at some point while leaving cloak in starting perspective.
BTNGoblinPrince Looks good, seems fitting for in-game use, as well.