Are you plnning on taking this guy into a sculpting package? That'll have some impact on your next step? Regardless, I don't think your mesh density is too bad at the moment. You could push the shapes a bit more here and there. Given the way your model is structured with the head inside the great big collar, you could…
@Joseph Silverman: Hey thanks for the vote of confidence! Here's the latest rev. I pushed some of the shapes a bit further, reoriented the elbows, added the collar lock, oxygen tanks, and a head. That head is just terrible though, I'm not sure my art style for faces really lends itself to dimension. I'm actually inclined…