Small planars and ribbons. I made a choice 40+ years ago. I've never changed my preference. 70-80s I really liked Stratherans ribbons. I made 3 set of speakers to fund mine. I picked the drivers up from Brian Cheney at VMPS. 20 24" ribbons.
I haven't found a single speaker manufacture that makes a line of planars or ribbon speakers at a 1/2 way reasonable price.
I liked the Infinity IRS Betas when they had rear chambers added to the monitor section too. One of the best bang for the buck speakers EVER made. The servo system and added rear chamber made them the right size for any room.
The size of the speaker in the room make very little difference if you design speaker cabinets to reduce resonance, and most of all not collect and deform the drivers face. WIDE baffles collecting distortion from all frequencies including the frequencies the drivers produce themselves is real good place to start.
Phase plugs on cone/voice coil drivers and servo controlled subs.
I don't mix BASS and vibration with my planar/ribbons just for the damage alone. I'm pretty sure most of the Ribbons will last as long as the magnets keep working and planars as long as the lamination holds up. 100+ years Then you can rebuild them..
BTW the Strathearns I built in the 70s were still going strong in 2010 when they were passed on to the son or grandson. They bought spare drivers from Magic Markey.
Bottom line they don't make what I like any more. SO I'll stick with what I got. Nothing better so far. Same wife for 49 years too.. :-)
Regards