I just plop the Jumbo Joe on a pizza pan (so ashes don't set things on fire) on a folding WallyWorld aluminum table and I have a grill on legs. If there's a picnic table or an iron CG grill it goes on those, on the pan.
There's a folding add-on grill grate that's a Big Green Egg product that may fit on the Jumbo Joe. You'd have to test the fit
For a portable grill I've had a barrell-style that mounted on the hitch that I burned the bottom out of, a Weber Go-Anywhere that was just too small, a Jumbo Joe, then I got a wild hair, sold the Joe and got a portable Traeger, now sold that and I have a Joe again. It feels right. When stationary for a length of time I've always used 22" Weber Kettles.