Advice on switching from a Denon PMA-915r to something else

Long time listener, first time poster. I wondered if anyone was familiar with Denon's PMA-915 integrated amp, and what amplifier would constitute a significant improvement if I were to upgrade? It's an old (circa mid 90's) amp, 80 wpc, THD .02 Class A MOS FET design. I think it sounds great, but am considering amps in the under 1k range, such as the Rega Brio, NAD 368 or Cambridge Audio AX80 as possible upgrades. Would any of these, or others at that price point make a considerable difference, or would I need to get into a higher price range?? I listen to a lot of vinyl. The amp is driving a pair of Monitor Audio Silver RS 6 speakers.

I would appreciate your thoughts. Thanks.
If you like the Denon sound, this was recently listed and very tough to beat for the $ even with  shipping this still comes in well below your price range.
Thats my listing let me know if you have any questions. Im just discovering how good Denon integrateds are thanks to another member on here. Sadly the 2000 is too big for my rack so im going with a newer more compact 160one.