Looking pretty good. I think I'd make a couple tweaks around those poles in rig cage.

You're going to have poles there no matter what, that's just the nature of that area, but I think you can tweak the flow a bit to get more natural deformations.

#1 I'd tweak it so you have a second loop [green-ish highlight on the right], better defining that lower edge of the rib cage, Its a pretty rigid structure, so you don't need quite as much geometry as you've got now, particularly the two bands [on the left below, highlighted in orange] feeding in to that pole.

#2 Denser geometry down here can can be used to form the natural crease when bending toward that side, its also an area that's going to stretch a lot when bending to the opposite side, so a little more geometry is probably beneficial here.

I think one loop [blue] to define the abdomen should be sufficient. The two loops you have now, looks like it might be rolling the start of the obliques into the abs [tho, its a little tough to tell from a single static image], when the obliques should be a more north/south muscle group.

Otherwise, looking good. Shoulders? UGH! Have fun with that!

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