upgrading my integrated amp

I'm looking to replace my Rega Mira 2000 and make a jump up at the same time. My current system is the Mira amp a Rega Apollo and Totem Sttaf speakers using PNF interconnects and biwire speaker cable. My room is approx. 12' wide, 16' long, 8' high. This would be the first step in some other planned upgrades ie. a dac and upgraded cables.

Amps that have caught my interest

Rogue Audio Cronos or Metis/Atlas Magnum combo
Unison Research Primo or Secondo
Rega Elicit
Blue Circle GDC or DAR

I'd appreciate any comments or thoughts from owners or people who have had experience with any of the mentioned