Is there measurement that correlates with cohesive/pinpoint imaging?

I am currently using single-driver Omega alnico speakers which have the most coherent imagining that I've ever heard.  However, if I wanted to compare them with other speakers (including multi-way speakers with crossovers) in that regard, are there any specific measurements to account for?  Would measured delay between driver signals in a multi-way speaker be a useful proxy?
The problem with attempting to use head transfer functions at the recording level is it requires near perfect playback setup (specific to the recording unless you are using headphones), and not something readily or even achievable in most people's playback setups. Until we substantially change the listening system away from 2 channel speakers, we are pretty stuck with that is possible though advanced DSP algorithms and controlled reflections has promise in advancing what is possible with 2 channel. Sorry, analog just is not going to cut it for those advancements.
It’s funny how how people like djones and others accept that something exists without measurements to prove it when it suits them. Yet when it comes to cables, etc, they use the lack of measurements as proof that cables don’t matter. Same thing with gene at  audioholics. Always talking no measurements for cables to prove anything, yet anytime I ask him about showing measurements for imaging, timbre, etc, he goes silent and disappears. 

I have measurements in REW which shows a nice smooth curve over frequency from 20 hz to 20khz. If the speakers lacked coherence it would show at the crossover points. They were really pretty good before the filters but they did help especially below 200hz. I don’t recall saying something didn’t exist without measurements. I think it was more measurements show it isn’t audible. I don't know if measurements can show timbre I believe there would need to be a blind listening test to see which speakers reproduced the sound of a violin or saxophone more realistic.
IME, speakers with good measured step and square wave responses tend to image well.
Within a frame work of two channel audio, it is not simply timing information that is important, but relative timing information, i.e. the time difference between arrival at both your ears. To that end, a large baffle will not impact the primary wave front timing differential between a signal from one speaker to both your ears. Maybe you meant something else?

Time and Phase. Study how the highly evolved ear brain function to localize food and threat sounds and you will understand it is small timing differences. Add in low diffraction because a large baffle destroys time information while functioning as a mechanical averaging machine ( frequency response )