A little character design

One of the forums I frequent runs a bunch of little challenges for their members to practice & learn from. They range from character design challenges (such as this one) that last about a week, to full blown animation contests that can last months. I've never really participated in any of these challenges, but I figure it's time I start. It's a good source of motivation & practice, so I will really try to get involved in more of them.
This particular challenge was a character design, here is what we were given: Name - Diamond Dan Jewels, Occupation - Jewel thief. Personality traits - intense hatred for mickey mouse. Looks - must wear sunglasses & carry a knife.

With that to go on, and having seen numerous other people's versions of this character, I decided to start off with a simple diamond shape. Then I made another one upside down, like a mirror image, and from those 2 diamonds (in green on first sketch) I made the head & face, which began looking a bit ape-ish, but I decided to roll with it. I got a couple good (I think) loose sketches of him in what I think is a pretty strong pose. It is for me anyway. I think I actually captured a "line of action" so that's a step in the right direction. I'm not thrilled with the colored version, but that wasn't the point of the challenge, & I painted it without too much thought or effort. Anyway, here they are, I will add a link to the thread with other challenge entries, but their site is down for an upgrade at the moment:
Diamond Dan Rough 1
Diamond Dan Rough 2
Diamond Dan Colored