I own the Pass INT25 and use Tannoy 15" dual concentrics.
Your speakers I have not heard but they sound very similar.
I have an older Luxman Receiver in use in my office and
I like that as well. I do not see the differences that others
mentioned here.
I have heard Luxman INTs recently at $5k and at $10k.
In my mind they sounded excellent. Of course they were in well
setup rooms with excellent speakers.
You can buy Pass gear with a trial period from Reno Hi-Fi.
You do not mention a specific goal so I assume it
is overall next notch up for SQ?
Have you considered a Tube INT?
That would produce a different sound
and since you like the soft, big sound
you might really be happy with a tube INT.
The one I have my eye on in the new ARC I-50
at $5k. I am waiting for my mentor to listen to it
and advise me his thoughts.
Post more in the future. I like your system!