I don't have any pictures. I saw 2-3 bad ones while I was tech inspecting/judging in FSAE Italy last year. There were also other wheels made in the same way but with a thicker laminate which seemed ok.

Yes, its a difficult thing to define a load case. I chose 25% on the assumption that 50% of the driver weight is reacted by the belts and each side of the wheel evenly reacts the remaining 50%. Its almost impossible to define properly but I don't think this is critical. The stress values that have calculated are so high that even with a +/-100% error in the loadcase, the stresses are still going to be too high for any composite.

The simplest way forward would be to ban brittle materials in the primary structure of the wheel. Perhaps with an exception if you can prove your wheel will survive some defined impact load.