I think the High End fair in Frankfurt that starts next weekend will have a lot of new 4K AVR's, I have heard from people at Marantz/Denon that they will release some models then, that will begin to sell in June in Europe.
I myself have been holding out for a HDMI 2 compliant preamp preferably whit well implemented Sabre ES9018 DAC-chips, that doesn't look like a huge ugly black or silver box. And please no more blue leds!
Lindsey Stirlings music is now available on Spotify in Sweden, so I have started measuring the tracks. Most bass is focused around 50Hz in a few occasions on "Crystalize" it gets close to my +50dB bottom line level
I think more and more high-end 2-ch preamps will have built in DAC:s and even HDMI on some. I'm thinking of going that route a nice looking simple, and userfriendly preamp and then hide something like a Marantz 1603 for surround channel handling.