You realize, of course, that making convincing people is the hardest thing to do in 3D software. You might try to fake subsurfing scattering for the skin, don't ask me how. Maybe you can generate an extra layer of fold-like structures for the clothes in Terragen, and apply them gently over the folds that already exist. By the way, I saw your work in the Limburgs Museum a few years ago, in fact, this was the most important reason for my visit. It's incredible that you've managed to do this. My compliments!