I think it looks lovely. Agree that a bit of pale blue/green with pink flowers would really lift it from great to awesome.
You could make your life a bit easier by painting a piece of paper first, then cutting it into sections and pasting the walls and adding glazes of shading/stains etc at the end. I know that's annoying advice to get now, but it would be more manageable than trying to paint a pattern on the existing walls...
Also just going to mention a little bit of a scaling problem (and something I suffer with on my bases) - the skirting around the room is almost waist high on your painter. I know he's a dwarf, but if you cut the skirting in half length and height-wise it will be much closer in scale.
(Sorry, I'll stop now.)