Nice looking fly and nice colors. I especially like the use of what we in the western U.S. call kingfisher blue hackle (those in the uK and eastern U.D. and Canada know it as silver doctor blue; however, here in the western U.S. what is called silver doctor blue is actually what you in the east and the UK call silver blue blue).
However, it looks a little out of proportion because the rear body section looks too long. Keep in mind that when tying a multiple section body with joints (like this fly) the rear section has to be a bit shorter than the front one for them to ballance each other. This is due to the hackle hiding the very front of the front body section.
The fly can also be dressed up a bit and have a bit more movement if you wrap a small hackle 3-4 turns right in front of the body joint.