Chickens really do best with access to the ground in their run.
Most people let them have the fun of destroying the grass (or whatever vegetation there is), then using some system of bedding to control the poop. My personal favorite being Deep Litter, an actively composting mix of organic material.
Protection against digging predators is best accomplished by either burying wire mesh about 12" vertically or laying a wire apron about 18-24" horizontally on top of the ground (cover it with mulch or let grass grow up through it).
Pavers aren't effective as an apron because, unlike the wire, they are visible to the predators. Because they are visible the predators just back up and go under the pavers. With the wire apron they dig right at the base of the visible wall and can't figure out why they can't get through.