Nice sketch. Love the touch of the genetic modification of the wings.

I think you are pretty close, but I think the back haunches have more axial rotation than some of the species with reverse knees that we are used to seeing.

Not quite the same range of motion as a human shoulder rotator cuff, or hip/pelvic socket rotation, but enough so that when they are climbing they can spread their legs and reach pretty far for a hand-hold, with the accompanying muscle types and insertion points to be able to theoretically lift themselves using any of their limbs.

I am still working on my sketches as well; I don’t think I have the back legs down perfect, either.