Upgrade from NAD3020i

I have used a NAD 3020i as my amp the latest 10 years.
I have not found any amp that can match its details and treble.
Though, since trying a NAD 319 dedicated power amp in my system I realise that the 3020i lacks definition and power in the lower frequencies.

I wonder if anyone has a suggestion for an upgrade from the NAD 3020i. I don't need an integrated amp since I am using a receiver as a preamp. So I guess a dedicated power amp is preferable, although I am open for integrated amps as well.
Is there a dedicated power amp version from NAD of it from the same time or maybe later? (I have tried to research this but I cannot seem to find any info.)
I have looked at the Mark Levinson 23.5 which looks promising in sound, but I never seem to be able to save up to the $3000-4000 needed for one in good condition.

My speakers are Intelligent Sound IS8 mk II which are incredible at reproducing detailed and "naked" sound. My source is a PC with a USB DAC streaming mostly from Tidal so I need to match the quality of both source and speakers.

Best regards/David in Sweden