Add 2/3 channel Amp to Arcam AVR 750 Receiver for better 2 channel sound?

hello all,
I have had a Arcam AVR 750 (receiver) for 5 years and it is excellent and much better than the high end yamaha-marantz receivers I have had/have. As much as it is excellent for home theater sound ,it sounds very good but not as good in terms of separation and holographic sound I used to get with my ADCOM GFA 555 amp which I used for two channel. I am now wondering how to get better sound if I buy a 2 channel amp and use the preouts on the Arcam. Wondering which amp would make the Arcam sound better for music? Budget is around 1K to 2K new or used. Thought about Emotiva, Outlaw, Rotel products but wonder if it will make a difference or do I need to go for a higher end amp? Arcam puts out 120 Watts per channel. Thanks for looking..(Speakers B&W CM9 and CM Center)