Very cool. First time hearing about your project.

If someone steps on that, they are probably going to go through. The membrane looks solid, I don’t know if with heat or age if a hole could form. When we reroofed my garage, we didn’t leave any holes like that. Any soft spots got resheeted in plywood. Small gaps are probably okay, but that looks like 1 foot+

Tried this because of your comment. It’s really fun!