Yeah the model looks a lot nicer and cleaner than your original. I'm not sure but it looks like you might have some faces with more than 4 sides though. Also for the new UV map I think you could over lap a lot of what you've got there to give you a lot more room for texture detail. Since its mostly flat edged shapes you could practically piece it together like puzzle and have very little empty spaces.
How come you can't texture it?