Ok, my paintover of the front view:

(19 colors, vs. 20 colors original.
- used a more neutral background (this is my favourite, a greenish orange with only a little saturation; almost like a drawing paper) - don't underestimate this, it's important for being able to pick the right colours, do the outline correctly, and it will prevent your eyes from becoming sore).
- more contrasting values to make shading stand out more
- even though pants are "black", used 2 colors to shade them
- made his neck a little shorter, and his shoulders and hips wider
- added some muscles
- made him look less symetrical
- reshaded him
- bigger hands
- made him look less cleanly shaven
- redid the face's outline
- gave him a sword

(19 colors, vs. 20 colors original.
- used a more neutral background (this is my favourite, a greenish orange with only a little saturation; almost like a drawing paper) - don't underestimate this, it's important for being able to pick the right colours, do the outline correctly, and it will prevent your eyes from becoming sore).
- more contrasting values to make shading stand out more
- even though pants are "black", used 2 colors to shade them
- made his neck a little shorter, and his shoulders and hips wider
- added some muscles
- made him look less symetrical
- reshaded him
- bigger hands
- made him look less cleanly shaven
- redid the face's outline
- gave him a sword