You know, I had this same problem with my characters and I think I found a good solution that is pretty quick. In your 3d app, simply detach the limbs that you want to repose. Detach them at the shoulder and at the elbow. Then, repose the detached limbs to your liking. Next, reattach the limbs. Now some tweaking will need to take place. To do this quickly, simply bring the model into zbrush and sculpt the joints with the move tool until you’re satisfied. The whole process shouldn’t take more than 20-30 minutes maximum I think.
I really respect you as an artist and I know fully that you have far more experience than me. I just thought that I would throw out this tip in hopes that it would help you in some way. Great work man!