My two cents and completely my own view since this is a WIP.
It does scream "Classic Superman" - however, I think there's too much musculature around the mid section.
While Superman legitimately should be this muscular, I think when you take it from print to paint, and depending on the painter, the musculature will be too overwhelming. In my mind he's still in a uniform of sorts.
Personally, I would soften the muscles just a bit...but again, that's just me.