Martin Logan’s do space and purity, but like omni’s are not ideal for organically solid full frequency imaging. one reason is that the mid and lower bass uses dynamic drivers, a different type of driver, so the coherency in the low frequencies is reduced. this detracts from imaging.
a more traditional 2 way dynamic speaker system might be best for this priority. it makes the fewest mistakes.
imaging is about room<->speaker synergy, and room symmetry, combined with surface treatment of reflections. to get imaging that is ’right’ also requires that the room has good bass balance, so images are cohesive, and contain full frequencies.
with your budget, there are any number of quality 2 way speaker systems that can work.
do you have a dedicated room?
is it symmetric? how high is the ceiling? can the ceiling be treated?
windows or screen next to or behind the speaker?
any distortion in your signal path or speaker will restrict imaging by locating the sound coming from the speaker. so eliminating distortion anywhere promotes imaging everywhere since the signal transparency disconnects the sound from the speaker location. you hear less distortion, more of the music signal.
seating position will also be a factor. sitting in the near field and working on toe in and toe out will allow you to optimize imaging. near field means more direct sound, and less reflected sound. an advantage for imaging.
all these factors will effect the potential imaging of your system.