Well I think the colours are fine. They're supposed to look chalky and dulled down. Bland would be if they are the same shades and boring. This sig has different varieties of colours but they just don't stand out much on the page.
The colours are perfectly fine. Its never a bad idea to extract your colours from the picture itself. Anything more colourful and it wouldnt fit. On the other had I really dont like the background. Replace it with plain white. And do what Frag said, put some of those colours behind her. AND, I just noticed he borders on the sides, They NEED to be removed, please!