I'm hopping on to the i lova ArtistArticle14308.jpg bandwagon, it's bloody awesome. There really isn't so much to crit on that, but you might want to check out the ellipse in the wheel, it's kinda skewed unless you wanted it that way.
The old pages you scanned look good too but i think you have really improved since then
Btw, how would you feel about participating in a weekly activity inside our ssg? Staylor made a post about it in our Forums in Conceptart.org 3.0 group forums. Check it out and leave your opinion.