I have 2 15 amp circuits, one for the display, one for the sump and 1 20amp circuit for the back up heater and the chiller incase one circuit goes down the backup is on a separate circuit. I was also thinking about having a dual return pump and having the second return pump on the second circuit.
Is it overkill, yes, do I need it, no.. but in an open wall basement it was super easy and cost about 100$ for all the extra protection and now when I upgrade the sump, circuits are done. Just have to install tank and add water lol.