high end speakers? ... not sure what brands/model

Vintage enclosed speakers are far from good also.
At least horns can be tailored and tweaked as and when
newer better cones become available, and are easy to install.
Horns have stood the test of time, I mean how many boxed speakers from the 80's and before sound good today when compared to the latest speakers?
When one has bought a mega expensive enclosed boxed in speaker, one is stuck with its sound.
A good horn is most certainly musically comparable to any enclosed or panel loudspeaker, and in some instances are musically superior. IMHO.
To say one hates horns, is a bit like saying one hates Toyota's.

to put things in perspective, if your paradigms were a car, they'd be a honda accord--an excellent, tops-in-its-class all-arounder; more than enough car for many people. to get more perfromance and refinement, you'd need to pay a 50% premium for say, a lexus or acura. the question for you, of course, is whether the upgrade justifies the cost.
that said, if you're looking for more low end energy, i'd check out proac or naims own allae/arriva, which sound great with naim amps.

I hate Toyotas.

;-)

All I can say is don't get caught up in all the hype and always let your ears be the judge.

I perfectly understand why some people hate horns. But horns done right can be an extremely satisfying long term solution. For me: if I knock on the side of the cabinet and it sounds like a plywood box - I keep looking. This characteristic is often (but not always!) resonated by the driver in the cabinet and even my abused hearing can pick this up (and does get annoying after a time and I feel contributes to some horns bad rep). Tractrix as opposed to exponential shape for mid's can be a plus too. The efficiency with detail sold me.
Good Luck, you have an exciting quest...