I agree with @
der_Asiate.
To me, there's no good reason to have 3 or 4 mid-fi (or upper mid-fi) headphones.
Except if you need a closed set and an open set.
They'll all sound quite similar after a short while.
At first you might find some pleasure in comparing them and
picking out their differences. But that pleasure wanes quickly.
I suggest - I urge you to reach and put your resources and interest
in a truly fine headphone. A better Audeze, or Grado perhaps -
such will, I believe, make quite a dramatic impact. You'll hear
things in your music you've never heard before, the location of
various instruments will become more precisely defined, the
soundstage itself will be presented in new and different ways.
It seems from your post that you take your music and gear
seriously, so again I urge you to take a few steps up - even
using your present amp and sources - and enjoy a higher
quality experience with your music. I'm not a betting man,
but I might just bet on this: you won't want to go back to
mid-fi.