I would love to help in some way on the PS4 side of things if I'm needed. Although I don't do much here with NoDo as far as the actual racing goes, I do feel like I have some pretty good knowledge when it comes to creating tracks.
To avoid the issues you had before would it maybe be better to require a youtube video showcase of their track to weed out the lower quality submissions to lessen the load on testers. Also would add an extra step so people who aren't too serious about it might not do it and would make for overall fewer lower quality submissions. Pretty much every creator I know has the capability to do that or at least will have friends that are able to help them so I don't think it would exclude anyone.