Well, I think the most impressive thing is the volume of work you have in each update. That's a ton of work in a small amount of time.
But anyway... On the card illustration above, the dwarf guy in the back has this sort of 'flat' look to his arms. Not to mention the fact that he's a dwarf and he's really tall.
Well... maybe he could be human (hadn't really put that together).
Anyway, some good solid reference for that guy would probably be beneficial. I'd suggest if you have the time to keep on doing figure studies (especially life drawing if you have that option).
The violin girl is amazing... especially the style you've conquered it with!
The ages past illustration looks incredible too. In a way that type of illustration looks completely different from the latter cards you have near the bottom. Perhaps you've taken more time on this one? <shrug>
Hey there. Really awesome sketchbook. Very inspiring. I wish I had any valuable words for you. But you know what your doing. I'll be following your porgress from now one so if I have anything worthy to say I'll share it with you. Keep pushing! ;3