I'm working on a game project called Dungeon Fling and I could use some opinions and advice on the art. I am kind of stalled out on the project at the moment trying to figure out what I should do for the art. It has been under slow development for a couple of months and I have been putting off a lot of the art for a while now, and I am trying to finish up some of that but I am hitting a few issues.

The game is a dungeon crawler that uses minigolf or shuffleboard style mechanics. The player and enemies are represented as discs, and the player shoots through the dungeon, bouncing off stuff to get around and try to get to the next level.

This is a screenshot of the game as it is now.

I also have a demo up here http://www.newgrounds.com/dump/item/1403f97c016aaf7b47ee017242708c84

I'm aware that a lot of the art is pretty bad, some things like the pit trap are badly scaled up just because I was trying to save time in development. That is definitely not final. What I am really focusing on right now is the player and enemies. Right now I am shamefully just using  scaled down images of the concept art. Ideally what I would like to do is have an icon that looks good at that size, and potentially have a full body sprite that doesn't rotate with the disc but instead uses animations and multiple directions.

Here are some of the ideas I have tried. Most of them are pretty rough, I was just trying to get an idea of what I could do at that size.

Here is the concept art I am basing them on for reference http://ludopunk.com/wp-content/uploads/2013/07/warriorportrait.png
This is the shameful disc I am using now, not pixel art at all.

If anyone has any comments or suggestions for making these discs look good it would be greatly appreciated. Trying to figure this out has slowed my project to a halt. I'm having trouble fitting enough detail in that small of a sprite to make it look much like anything.
Thanks for any comments!

I like it a lot. I think the palette works together pretty well for the most part.
I just have a few crits for you. The could use a bit more attention to perspective, right now it looks almost like its laying down. Maybe try having some branches pointed toward the "camera. It also looks kind of strange that it all seems to bend in a ) kind of shape.
Also a smaller issue, the blankets on the bed look very round. I think that would look good if you had a character in them, but right now it kind of looks like someone built a blanket fort or stuffed a bunch of pillows in there. I think if you just square off the corners more and flatten out the light on top it would look fine.
I could probably point out some other issues but overall it looks pretty good, I like the feel of it.

Thanks for the comments! I'm not sure what anatomy issues you are referring to, could you expand on that? I definitely need more shading on the background stuff, I'm just trying to figure out how to do it and make it work with the whole tile thing. I plan to start working on this next week after I finish with ludum dare.

Version 3 is definitely on the right track. The bigger eyes helps a lot. I think one thing that is making it look strange is the symmetry, it makes it look like a mugshot. If you look at most portraits the subject is not looking straight ahead. Even in that photo he is looking straight ahead but his face is far from symmetrical. Just a thought, I look forward to seeing your progress!