Thats some major poly-scrubbing your asking for, Flyingdebris... Your going for the TRO 3058U version, right.
A Bigger Backpack, and also beginning to devide the back of it. That will mean bigger shoulder,
i.e. the topmost (round) part, this will also help the the lower part of the shoulder to work properly). But (by the above corrections) the whole shoulder should the be remade at the part facing the Backpack, for added moveablilty.
Lowering the armpit, will result in a lengthening of the upper arm, overall. If that is done the torso needs to be lengthened too. Keeping the elbow by the hip!
Opening the knee-part up, to show the knee more, will also help the animatix part on the upper- and lower-leg.
The addition of a plate above the foot might work, but then the lower leg has to be more open at the foot, else the added plate will cause it to scrape on the lower leg.
Less ponty Claws, Claws are for shredding. The Claws are fine

All good suggestions, Flyingdebris, [are you on Deviantart under that alias to?].
Regardless of the above scribles I donīt think that the model needs any rework. It has the touch of Spyro.