I have been working on this sprite for a couple days now, and I'm having trouble with it.

Self edit:

Edit 2:

Edit 3 (color edit for darker/melancholy theme):

Edit 4 (color edit):

Edit 5:

Edit 6:

It is an isometric RPG soldier (modern/futuristic) achieving for a dark theme.
A) I can't decide whether or not to just outright rip out the outline or leave it
B) I feel there is shading issues, and various others I am not touching base with
C) There may be some angle issues.
D) Possible pallette issues? If there would be a more interesting pallette, that would be awesome to use.

C&C is welcome, if not desired. I would really love some edits to demonstrate what I can do with this, correctly.