I too use a small dustpan and brush, it's only 3", just right for sweeping corners. I leave the grass and move the run. The lawn mower picks most poop up.
I put on pair of rubber gloves and do the poo patrol on the grass by just picking it up. If done regularly it doesn't take long. Then I use it to fertilise my rhubarb! Which btw the piggies have no access to.
I don't know I make the other half do it. Lol
Haha the poo machine!
Get a dog. My spaniel (rip) used to love eating guinea pig and rabbit poo!