Congrats on retirement, I am three years in and enjoying it very much. And a nice system, I too have the Reference One’s, a very capable speaker. How is your listening time split between analog and digital? Any plans to add streaming?
If you are leaning towards digital, then a separate DAC is a consideration. Unfortunately the Mimas does not have a preamp input which would allow you to experiment with some different preamps. I have been on a preamp quest for the last several years, and it is certainly a large part of determining the sound of your system. I recently upgraded from my Pass preamp to Audionet, this has been quite a revelation.
Not sure what central Wisconsin means, but I am in Duluth if you want to hear a different front end with the KEF’s. You are welcome to visit.