A very clean, stylised set of pictures there! I do like them.
The aspect I think I enjoy most when I gaze upon these, would be how smooth everything appears. Your use of shading and colouring really makes these pieces stand out, and I do one day hope to also be able to produce art of this quality. But that involves practise I suppose :P
For now, I can offer you no critique, as I'm not sure as of yet where you could improve. In the meantime please draw more and post them, they look wonderful :)