Please let me know if I am on the right track. The end result is to increase the sound quality in my 2 channel listening.
IMHO, for a significant sound quality increase in 2 channel listening, you should be looking for a 2 channel preamp with HT bypass to eliminate using the AVR as the preamp for 2 channel. This has been discussed many times on this forum, and the ones that added the preamp respond with comments like, "Wow! the speakers came to life."
I not saying to forget about cables, but just that they should be secondary. Improvements from cables will be small compared to what you will get from a dedicated 2 channel preamp.