He reminds me of Shrek, which is never a bad thing.
Animation is gona be hard if you going to shade him this detailed. If you look at disney and other cartoons you'll notice they barely shaded at all.
About the character:
-The arms need to be consistent in terms of width, they look thinner in some spots than others.
-It seems your trying to get a realistic metal look on the sword and shield, this clashes with the cartoon feel.
-Eliminate the double pixels, look at some Anti Alias tutorials. (note this might take away from the vivid cartoon feel & r it might just actually enhance it.)
One I googled I didn't read it though
http://www.natomic.com/hosted/marks/mpat/aa.html- I'll be more concerned about the jaggy edges, try and smooth them out.
- The highlight color used is to close to the overall green and is lost, it makes visually little difference if any. You might want to change it to a lighter green or mess with the colors a bit.
-Stomach looks like a rock under his shirt, it needs to be like jelly rather. meaning wobbly and soft, no hard edges like the top left. Keep it rounded.
There is a sticky somewhere in the forum I think its in the C&C thread that have some nice tutorial links.
Goodluck I look forward to seeing the update!
Ps: If I find some time i will look into fixing some of the issues I think there are. Don't count on it though i barely have time to write these comments out atm.
~Afflict