My room is slightly shorter than yours, 20' but the exact same width. I have a flat 8.5ft ceiling. My equipment is set-up in the manner you're considering. I keep my equipment on two low racks between the speakers. But for the distance from the side walls and rear walls mentioned by Nsgarch, I agree with everything else he said about speaker placement, seating position and long narrow rooms. On the distance from the side and rear walls I think you need to experiment. It depends on your room and speakers. I have my speakers about two feet from the side walls (measured to the center of the drivers) and 39" off the back wall (measured to the front of the drivers) with very little toe-in. My seating position is 9' from the front of the speakers. All very close to what Nsgarch suggests. I have found this room set up gives the best soundstage and frequency response. I also agree with Nsgarch that the way you have your room set up now is probably the best. If you were running balanced IC's for that length into balanced equipment, I'm not sure you would lose more than you would gain from the change you are considering. Depending on how much noise if any your 25' RCA IC is picking up or if your preamp is having trouble driving that length of cable, it might be worth at least trying it. As I said, that is where my equipment is and I have very good results. But if my room would permit it, I would be inclined to set it up like yours is now, but my system is fully balanced so the long cable run is not a problem.
The long / Narrow room - system configuration
I have always and still do have a longish (23.5 feet) and narrow (12.4 feet) listening room. I have always put my speakers on the short wall with my monoblocks and run a 25 foot long (rca) interconnect in between my amps and my other components which sit away on the long wall down by where I sit to listen. Have most chosen to give up on this type of configuration in order to go with much shorter IC. I would have to move all my FE components which sit on a fairly massive Rix Rax Hoodoo and move them all ( including turntable)
in between my speakers. In most of all your experiences, would what I gain in shortening that 25 foot cable be worth it if I then negatively affect my soundstage with a big ol rack full of my FE components between my speakers.
in between my speakers. In most of all your experiences, would what I gain in shortening that 25 foot cable be worth it if I then negatively affect my soundstage with a big ol rack full of my FE components between my speakers.