We've been on the Trace several times. It is faster than many other routes even if it is far slower.
There are a couple campgrounds on it that will accomocate a large RV, now, I understood, from a post or posts made last year.
Otherwise there are two near Tupleo. We stopped at many sites each trip. Get a brochures, fronm Natioan Park Service or online and info on campgrounds, off the Trace if you plan on linger long.
There is a great Lake for fishing on the Trace. Probably have to exit at Jackson Miss and back track to find a good launch site and campground.
One or two places you can park and fish from shore.
Watch the fire ants. After leaving the trace and going west check out Poverty Point State Park. Nice RV Parks.