Excellent points Joystick!
The ultimate for me on each input apart from the excellent filter suggestion and "mono-ising" at distance would be the inclusion of a
simple delay for each input so we can do haas style panning. If the delay could be smoothly modulated/interpolated via automation too then that would be so so good!
I already use a haas panner plugin before reassuround connected to two different inputs on reassuround and send the same sound to to both inputs, put one front and one back and then alter the delay in the front opposite to the back. The sense of the sound moving through the middle of the room is very powerful compared to volume alone. It's frowned upon for big theatre systems that can have big delays due to a listeners seating position in the theatre but it's still amazing
Having that in reassuround would save a lot of time and allow even better setups of it (plus the one I found still has some zipper noise to it when panning)
Perhaps the delay could be a part of every channel but the "panner" would be in the edit all knob area and would then work to delay oppositely even/odd numbered pairs of grouped inputs. There could even be a new "T" button along with X, Y and Z to do the inverting of time for the link delay
That way you could group 2 stereo inputs (4 total) and do a haas pan on them very easily