Rating: 7 I don't like it. ... Normally I'm a big fan of your work... but if you're going to reference the artwork for the character, then the conversion should be an attempt to follow that artwork. Your model has different head, jump pack fans, different details ...
Just doesn't feel close enough to the artwork to merit the reference... I'd probably feel better about the conversion if you'd not put the sketch in with it.
Also... most of your marines are helmet-less ...why is that ? are you not a fan of space marine helmets ?