Wide dispersion + high efficiency + detail + coherence in a speaker?

+1 on the Ohm suggestions. I have had the 2000s since 2009, and they provide as much of what you’re looking for as possible in one speaker. No, they do not project laser sharp images, but there is image specificity within a very wide, deep and tall soundstage. The bass is extended, solid, and accurate, and they are pretty easy to place. With the right amplification and source material, the dynamics can be nuanced and explosive, IME.  They are not, however, very efficient (~87 dB sensitivity, IIRC). But they do quite well exposing fine detail without becoming etched or overly bright. And they are very affordable (the 2000s are $2800/pr). You can read my full review of the 2000s here on Audiogon in the review section. Over eight years of listening to them and I wouldn’t trade them for anything I’ve heard under $14K. I do run them with subwoofers, and they respond well to improvements in the signal chain (I have upgraded most of my system since I got the 2000s). Forget the preconceptions about omni designs people who haven’t heard the current Ohm Walsh speakers will tell you, and hear them for yourself. Ohm offers a 120 day in-home trial.

Bondmanp +1

++1 mapman! I have a pair of the older Walsh Sound Cylinders (with the 8 inch drivers). In use for 10 + years now! They do indeed sound AMAZING - a wide open 3D sound from anywhere in the room!

I like the JBL recommendation so far.

regarding ATC - wonderful speakers but they come to life only at high volumes.

the efficiency thing is about immediacy! That is the magical word that is important in HiFi !

Coherence and dispersion = Revel. But not efficiency. Efficiency plus coherence maybe Goldenear Triton; anything with the powered woofer (3+ and up). No efficient speaker with coherence and dispersion comes to my mind. Zu may be efficient and quasi single driver coherent but forget dispersion. And frequency response curve is a deal breaker for me. Good luck. If you find a real answer lemme know.