Protecting the paint…after posting this the other night I got to thinking about how I might tackle this. I was thinking about using silicone caulking and brush and just painting a thin layer across the bottom of the magnetic feet. It might need repairing but should remain quite soft over time. I also thought about the rubber dip used for making grips for tools such as pliers.
As for the four way PVC, it would actually be thee feet on each base. Here's a pic of the * I was thinking of:
I don't know if that would work better than four, but I believe it would.
Still, nice execution.