Hello @rost ,
I had the Bluesound Power Node for exactly this application with older KEF floor standers in both my dining room and later in my master bedroom. It fits the bill exactly, sounded fine, and can be fairly easily sold if you upgrade later.
I will say the big speakers were a bit of an overkill for a third system. I eventually sold all that and bought a Naim Muso 2 for the bedroom which sounds quite amazing, is elegant and a partner please vs the big KEFs.
Today,, the Muso is gone and I run a pair of Sonos Era 300 speakers, one in the master BR and another in the master bath. These also sound great for their size, much nicer than the older Sonos speakers. They stream Qobuz, where I have nice playlists and are rock solid on my WiFi. Don’t even need the app to bring them up, just touch the play button and things resume.