System advice

Personally a fan of Arcam, I feel it's highly underrated so going off that was a mistake IMHO. I’d avoid getting onto the cable merry go round personally. EIther go back to Arcam or consider Parasound or Luxman as good directions.

Go back to the Arcam if you liked it before.

OP:

I’ve been thinking about your original set up and what you were convinced to change to. Arcam and Monitor Audio are great, but extremely neutral. For many audiophiles they are too laid back and warm sounding. They crave the music to have some bite, extra emphasis in the upper midrange and/or treble. IMHO, B&W and McIntosh fit in this category. If you were really happy with Arcam/Monitor Audio (and I would be) then those giving you advice to go to Naim and other cables fit in this category.

You don’t have to crave the B&W / Mc sound to be a real audiophile. Get what you like and stick to it.

One of my most accomplished audio buddies is a fan of NAIM amps and preamp.  He pairs them with Focal Electra 906, and prefers the NAIM over some very good Cary tube gear. 

The most important thing is that you like the sound.  It's hard to say where the issue is for you, but it's always very personal, and of course interactive with the rest of a given system.  It might help if you could give some hints as to whether it's too bright, or too dull, lacking bass, booming bass, etc.  Have you tried adjusting the speaker placement a bit to increase or decrease bass reinforcement, and toe in?  I fine tuned my system with things like cables, power supply upgrades, placement, etc., and other stuff that's supposed to be barely audible, but yet it's made the difference between being good and spectacular with pretty much the same gear. 

Someone told you that Naim is better than Arcam. Wow...