A deeper more holographic soundstage.

Roxy,

Wow that was all a bunch of conjecture which each participant believes is helpful. Some possibly useful but most doubtful.

Heed the expert from Atlanta who wrote the book on improving sound. ($500/day per session) He tells everyone the 1st thing to do is move everything out from between the speakers. This is 100% correct.
If you can't move it then lower it.

In my setup every piece I play has the vocalist 4 feet behind the speakers. Perhaps I do not listen to crappy recordings but who does?

The rules of physics still apply. If there is not distance open to the wall behind your speakers you will fail.

On symmetry: Also a no. Reducing early reflections is everything.
The more symmetry, the more reinforcement of early reflections.

News soon to be common knowledge:
The Amp makes all the difference.

Sometime in March 2021, A well established, US based maker will be releasing a new &  affordable product which beats all other comers. No it's not Pass. 

Sorry for the teaser. 

I have not made that little since the early 90s.

Heed the expert from Atlanta who wrote the book on improving sound. ($500/day per session

My mechanic charges way more than that.

On symmetry: Also a no. Reducing early reflections is everything.
The more symmetry, the more reinforcement of early reflections.

While early reflections are very important the rest of this statement is nonsense unless you are breaking symmetry to fix a worse issue.

The rules of physics still apply. If there is not distance open to the wall behind your speakers you will fail.

The rules of physics still apply. This statement however shows a one dimensional knowledge of acoustics (physics). It's the different between knowing what you are doing and parroting rules of thumb from others.

My experience, not hugely vast, non technical, was; as soon as I experienced minimal  XO’s as in my loudspeakers (Reference 3A Grand Veenas), phase alignment, the holography went through the roof. Further enhancement was the made through the use of tubes and room treatment, (bass management and diffraction), in that order. Undeducated ears that listen in my home, always comment first on the imaging, even unknowingly whether or not that the recording was of low or high quality, just that they were familiar with the music itself.  

@roxy1927,

Do you think you are looking for a "realistic" depth of sound-stage or an enhanced one to suit your personal preference?

My Maggie’s do I nice job of providing depth to the soundstage as I’m sure other dipole and open baffle speakers do as well.  As others have mentioned, getting speakers away from the wall, room treatments, and the quality of the recording all contribute.