A year or so ago, I built 2 or 3 small deltas for E-power. They were flat wings made from Depron with LE and TE sheeting and capstrips of balsa, then covered with Ultracote. Wing loading was in the ballpark you describe. Launch was OK most of the time if I threw it hard enough. Power off, the glide was about the same as my car keys. The last one refused to launch, torquing into the ground no matter what I did. That was where I gave up on the concept. Too heavy.