I would want to add plugin called TB Isone to DSP and then listen to both headphones... I have already estimated the ideal settings for improving the perception of space and depth to my head and ears and my experience with phones I have had in possesion so far is that the more neutral the sound is the more natural the effect of TB Isone is going to sound. I still haven't been successful in assessing why is that but if I do not EQ phones to be near to neutral, the sound with TB Isone is very unnatural. This can be spot in the best way with treble... Incorrect treble response can completely ruin the experience - in my experience.
Yes, this is subjective to my ears but as I am not allowed to use measurements, I need to have an option to help myself this way for example... Another way would be telling you to let me listen to the highest number of genres and recording qualities. Neutral phones are going to sound the best, they are the only allrounders in theory and practice as well.
In my opinion, neutral sounding phones sound the best across all genres and sounds... However, you cannot beat subjective excitement gained with Grado in rock music, HD600 for classical, Denon for electronica etc. This can fool my ears as well... unless I am allowed to use my methods of assessing the phones.
I do not want to have the most exciting phone... I do want to own the one that is going to reproduce music in the most natural way even though it is not the best sounding experience with them. Of course, if those phones are going to be unpleasant to me in some way, I am going to help myself a bit with EQing.