This is how i take photos from my models:

About 8.00-10.00 or 19.00-21.00 at this moment sun doesn't shine too much and no need to use flash and i get enough satisfacting pictures. That Island of Blood box (yeah, almost every box can do this) just cause it gives flat white background.
And about your painting: Green looks good, enough layers and highlights, blue feathers and shoulder pad (or what ever it is) looks very nice too. And that power sword, i love it! Gotta try make something like yours because my blending looks awful. And like already said, that cloth needs more mixing like Brown-Bleached bone 100-0 -> 75-25 -> 50-50 -> 25-75 and 0-100. Yeah, it might feel it takes long time, but its actually quite quick job and looks really good. And small white dots on eyes.