There has been many a red robin actually. I think Tim is just the current one. In kingdom come (alt universe) a middle aged Dick Grayson hangs up the nightwing costume and becomes red robin. Google it, there are others.
The right leg (of him) its too curved, and I strongly suggest you to cut the whole canvas until the canvas itself be the one who cut the legs, so it looks like an american shot and not like a full shot with a robin with cutted legs. Besides that its a pretty good work. take care