I'd demolish the tombstones but take the photos and put them on museum information style panels lining the back of Future Word, around the path up to the Wonders of Life building.
Take away the stones, consolidate the blank spaces, and they wouldn't take up too much room, and if they're about celebrating good times in the parks, or remembering loved ones sadly lost, then Wonders of Life/Festival Center is a totally appropriate theme, and they might also help draw extra foot traffic towards Universe of Energy and not obstruct any view.