Which texture/material is the absolute hardest to get looking just right on your AI characters?
I personally find dark skin the most challenging, especially trying to go REALLY dark. Krea and Leonardo do a really great job at this with almost zero effort (especially using the Z-Image model), Nano Banana Pro with the right prompt.
(Stella Sky's Avatar DNA Builder outputs great prompts for all skin types, btw and they work great - see the first image for examples) What are your challenges in the texture department?