by all means use the electrician friend to add a few dedicated circuits on the quiet leg of your panel. IF he is going to use unused breakers buy new ones from a quality company ( Square D ), hab
ve him clean up box, check grounds, tighted everything. You can get Hospital grade Hubbel outlets for $30 and then the sky is limit....IMO $120 buys a killer outlet.
Room treatments - Call GIK Acoustics and speak w engineering sales person, they will advise on room. w your size room you are looking at about $2k, maybe 3... this will make a WORLD of difference....
get Jim Smiths book on better sound. Revisit your speaker setup using a precision setup laser ( Leica disto ) your speakers reward careful detailed setup !
Power conditioning for digital components, switching supplies and trash and has producers first. Here a Furman can be quite effective. I like the Niagara class gear for phono pre, but not Power amps.
You can easy trial PASS gear including used and demo gear with return via the dealer in Colorado...great accommodation
Used Sky interconnects validated by factory to be authentic would bring out nuances missing today.
have fun !!!! enjoy the music
Jim