Very nice looking bow. How much set are you getting? On a regular bow you expect a couple of inches, I suppose with a kids bow you would see at least an inch unless you are getting a low poundage right off the form as well.
I have had a devil of a time making kids bows too. My problem was using too wide a design, which made the limb have to be super-thin and the thickness taper too fine to execute properly. I finally got a shooter after going to about 1/2" width.
I've found that a R/D design seems to give me better results in the set department. Is that what you are using, or did you just flip the tips a bit?
And how did you draw that nice ellipse?