How best to arrange cables in this room...

@mmcgill829 

So is the fireplace a brick/block build or a hollow box with an insert? If the latter it may be possible to pull the firebox and run a large conduit across the base/slab towards the rear of the enclosure. You could sweep up on both sides to a j-box and pull your wire through. 

@designsfx That could be something to investigate.

@carlsbad2 

Yes, always trade offs. Best would be to use monoblocks located next to speakers and use long interconnects. I am really luck my system is no longer in a common area. 

While I don't disagree with what you say, I worry about loops of cable are the basic inductor shown in any electrical physics book.   It is a small inductor, but it is an inductor.

Coiling wire increases inductance, but coiling cable doesn't, since both wires in the cable produce magnetic flux in opposite directions.  That is how non-inductive resistors are woven (bifilar resistors).  It is also principle of common mode choke with inductance for common mode signals and zero inductance for normal mode (differential) signals.  In addition most of speaker cables' wires are twisted (would be stupid not to) and twisting greatly reduces cable's magnetic field for wavelengths much longer than twist pitch (wavelength at 20kHz is 10km).

As for uneven cables - if you believe that speaker cable affects the sound it will be proportional to length.  If it is inaudible to you, then the only think to consider is how hard would it be to sell them in the future.

@ghdprentice this is true. one of the amp options I am looking at are triode labs americano 45 mono blocks, which are pretty small form factor each and could possibly work placed near the speakers. A lot easier to hide interconnects vs speaker cables. Still deciding on whether I want to stick with integrated or go the monoblock route though, but that's a conversation for a different thread 😂