Years ago, component and ancillary changes in my second system yielded much less than the expected impact. After a while and many attempts to rectify the situation, I implemented my own version of your RoomTunes, made with burlap we sewed up stuffed with long-hair carded wool a local mill produced. The effect allowed the sound of the individual components and ancillaries changes to now come forward.
This allowed me to understand why price does not ultimately determine the system success. Folks often stress the importance of synergy in this vein, but the room and system setup therein prove crucial. Every one of us regularly hear systems made up of good components sound much better than systems composed of great (or more often, just more expensive) components set up / integrated less well.
Audiophiles fool themselves believing tone controls no longer exist in this hobby. Consider the countless dollars and discussion threads spent on the hopes for and sonic effect of changing whatever (loudspeaker, power / pre amplifier, tube buffer, CD player, turntable, cartridge) component, resistor / capacitor, vacuum tube, cable, isolation device, tweak, etc. in the quest toward the ultimate destination