recommends for interconnects?

An Option can be to swap out the Connectors for a OCC Pin Connector.

This can be further extended to changing the chassis connector with the same.

This can then be further improved by using PC Triple C wire inside the chassis on the signal path.    

I purchased some Cullen Crossover interconnects to compare with Audioquest Colorado RCA’s. I wanted to determine whether I liked silver or copper from the tape outs on my power amp to the inputs on my headphone amp. For me, the Cullen sounded better than what I expected. As far as the end game, I’ll purchase Audio Sensability’s mid tier cable. There price in US would be about $350.00 and they accept returns.

Good luck, for under a few hundred dollars.  But try Kimber Kable

It sounds like you've been given the snake oil that expensive interconnects change sound. They do not. Anyone who claims otherwise is not an a true audiophile. Their misguided, primed opinions do not change objective facts, physics, and the science of sound.

A few years ago, I was where you are (with regard to interconnects). Trying to extract an infinitesimal improvement to resolve an imperceptible (to the ear) anomaly. A sound tech friend recommended a book to help with understanding the concern I was describing to him... "The Audio Expert" by Ethan Winer (available on Amazon). I highly recommend it to anyone that has become "obsessed" with audio, before spending another dime on audio components.