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

@zuio --

Perhaps some older Tannoy Gold 15" dual concentric drivers would do the trick. Simon Mears Audio makes Tannoy Autograph replications with these drive units, refurbished and all, and they provide you a uniform dispersion pattern (much more important than "wide" dispersion, I’d say), true high efficiency (~99dB), detail/insight, coherency in spades, and great dynamics and bass to boot. They’re big and heavy, and will cost you at least or about $20,000/pair, but you asked for it without specifying a retail limit, and I’m giving you an example of speakers that may fit the bill according to your needs. Not least, they’re beautifully made from ground up to original specs.

As the OP goes:

...
Vandersteens have a tiny sweetspot
MBL are lifeless and are not coherent at all.
Ohms lack in dynamics and detail.

A rather unambiguous way of stressing the importance of efficiency (i.e.: liveliness and dynamics), as well as implicitly downplaying soundstaging/imaging (or aspects of it) compared to other traits - certainly if Vandersteen and MBL are anything to go by in this regard. Single-driver speakers are also mentioned by the OP, and so may point to a desired carrier of coherency here other than liveliness (coherency likely means different things to different people). Options may not be multiple, and some compromises are inevitably to be made. Nevertheless, should be a fun journey.