cleaning fiberglass roof top?

I've been reading the posts on how to remove oxidation from a fiberglass roof, but I am still at a loss about how to resolve my particular situation. I have a 2004 Roadtrek that I purchased used last year. The roof is badly oxidized, and in some places, there is no paint left at all -- just the fiberglass. It does not leak.

Has anyone had experience removing all the oxidized paint from the roof and re-painting it? Would it hurt to leave it the way it is?

Thanks,
Beth