Might be my best so far

 

I like what you've done with the glasses here. They have a nice sheen to them that expresses the lens and the eyes behind them. And I think you've done a good job of controlling the vibrant colours that you've chosen, giving the character a kind of citrus feel. The forms of the hair mass look good too.
As always the only thing to work on is the hard edges, particularly those around the collar. Just spending a moment cleaning that area would give the image a bit more impact.