I'm on a similar upgrade path with a similar sized room. I'm using a venerable KEF speaker from the '90's, the KEF Reference 107. I'm the original owner. They have been upgraded with better crossover parts and new internal wiring. I have struggled to find anything I like much better without spending a fortune, so I will be interested in responses. The rest of my system is CODA 16 amp, CODA 07X preamp, Playback Design Merlot DAC, (Upgrading to Playback Design MPD-6 soon), Innuos Statement streamer, and a stereo pair of REL S510's. . I find the KEF and CODA gear to be a really compelling combination! I would echo the comment about considering adding subs to your setup. You will like what they do to the soundstage and it's NOT about more bass.