looks rather cool, but one big error i see is one of most common in brushing, when you starting
the actual shade/light difference between colors is HUGE, which like creates two color blocks divided by small lighten up( or commonly white ) highlight
ill show what i mean, and post it

edit:
this is what i mean, hope it is some help, even when i did it halfassed and quick

Lots of help mate!
Really a big, i did notice the huge difference in tones and shades, was having a bit of a problem with it and didn't know how to go about it!

Will get crackin on it tomorrow hopefully!

More work on it today!

niceo work so far mate .. keep it up