AC Power

I have a relatively nice system, but have done nothing with my AC power, with the exception of upgraded PC’s and a cheap iFi plug in power conditioner. My question is multi fold… do I need to do something, and if so what? Dedicated line (15A or 20?)? Quality power conditioner? Both? Which one first? How do you tell?

My system is a combination of HT & 2 channel & I tend to use both simultaneously as I like to watch sports while listening to music.
My amp is (I think) a relatively low draw… Moon 330A, Rythmik sub, BHK pre, Aurender, Qutest w/Sbooster, R11’s. No high power amps are in my future & never listen above 75db. I do currently plug my amp directly into the wall. All my wall warts are gone. For my HT, add a 75” Sony TV, Marantz 7015 AVR & a Klipsch sub (although at zero volume the AVR & sub should not come into play).

I am considering buying the Furman IT-Reference 15i or 20i first as they are well reviewed & are priced very well on Amazon ($1,400 / $1,900). Before I pull the trigger, should I go dedicated power & at what amperage (my nephew, an EE & audiophile thinks I am drawing no more than 5 amps) as that will dictate the Furman model?

Interesting, my nephew thinks neither are worth the investment. His statement: “Do you have appliances on the circuit now? What kind of interference can they inject?...voltage drops would come from current draws...which trip breakers.
Not steady 60hz a good power supply handles. So it all comes back to was the power supply engineer dropped on his head as a child.”

”Personally I think it’s something audio people do when they have run out of gear to buy.”

Any thoughts or recommendations would be appreciated. Thanks!