Unfortunately, like most, you ask the question after you already spent your money.
The company that changed audio understanding of power supply is PS Audio. No matter what you think of some of their other equipment, they understand power and will clean up your power while non limiting your amp’s ability to respond to dynamic and bass situations. They are what others compare themselves too. May power "conditioners" do more harm than good. Some are just snake oil.
i recommend the Power Plant 10. This is one generation old but I saw an interview where Paul himself said "maybe the PP10 is better than the new PP12 for amps."
PS as for yoru home’s electrical system, one thing you can do without too much trouble is figure out what else is on the circuit with your system. Move as much as you can. Maybe there is a circuit 20 ft away with nothing on it and you could make get a 10 awg power cord long enough to reach it. there are inexpensive actions you can take. Figure out what gauge your house is wired with will help you usnderstand where you stand.
PPS Funny story Before I installed my dedicated line I had my system plugged into the wall. I decided to figure out what was on the circuit. Well the laundry room is behind the wall and the circuit was the GFCI circuit that runs to the laundry room, every bathroom, the kitchen, the garage, and every outdoor outlet. One circuit. Lots of junk on it.