Well engineered cables are all that's required IMHO but I may be wrong.
I totally agree. You can drive yourself crazy trying to find the "best" cables. I'm not sure there is such a thing in the absolute. Find something that works well in your system and within your budget and enjoy the music!
I also agree that you can get much bigger improvements in sound by optimizing your room than by switching out your cables or with other system tweaks. One could argue your room is at least as important as your equipment. Cables can be used to fine tune the sound of your system but should never be used to try to compensate for system or room deficiencies.