"the Q7 have completely different drivers (magnet)than rest of the range"
Highly, HIGHLY doubt it. Looking closely at them, I have no reason to believe this.
Perhaps you can try to explain the differences. But I believe there to be none of any significance.
"I believe that defining a speaker by the drivers material used is a bit simplistic"
Not as it pertains to this discussion. The EA sounds different from all the rest of the ceramic based speakers because it at least makes some attempt to preserve the time domain. (Ie. 1st order slopes, time alignment) THIS is the reason for sounding different from other ceramic speakers. But it does not eliminate the ceramic flavor of the EA.
I am quite experienced with all of these speakers. Of them, the EA is by far my favorite (because, considering the time domain, it is of significantly higher fidelity than the rest. This is indisputable.) But, try as I might, I can't quite get past the ceramic flavor that influences the sound.
The relative similarities of the type of things that MOST impact the sound of a speaker between the rest does, pretty much, boil down to driver material. Not exclusively, obviously, but is of very high significance.
The carbon fiber cones tend to impact the sound less than ceramic or aluminum, which is probably why I would gravitate towards Magico as a close second to EA.
However, for my expectations, neither are worth owning long term.