This was alright, however it got kinda irritating at some parts. I am not a fan of pixel perfect jumps in 3D platformers. It can be really hard for some people (especially me) to tell where the platform ends. So, on the first jump, I just have to guess over and over until I get there. My second gripe is the checkpoints. Having to wait for the moving platform to return is also pretty frustrating. I guess it's a penalty, but personally find it more irritating when game make you wait like that.
However, I love this idea. All you need is a tiny bit of quality of life stuff to aid it. A darker shadow or circle indicator under Jessie would solve the edge of platform problem. Slightly speeding up the moving platform would also help a lot, but if that must be a penalty, then I understand that as a design choice.
I think you should expand this one. Despite my frustrations, the idea of a world where you can get free stuff for doing obstacle courses is amazing. You could do a lot with it.