It's something I want to do at some point, but not something that's coming any time soon.
On the Nimbus SE, I haven't done the best job explaining its features, so it's worth mentioning that the added features are useful even without an expression pedal.
The Exp foot-switch combines with the Exp knob to work kind of like a second preset setting. So for example you could set a smaller room reverb up on the main controls, then set the toggle to Size and turn up the Exp knob to 3 o'clock. Stepping on the Exp stomp will now ramp the size up to a big hall.
The same settings but with the Exp knob up all the way will let you switch between your normal reverb setting and an infinite decay time, so it's like a "freeze" switch.
With the toggle set to In Level, you can use the Exp switch as a buffered bypass that preserves the reverb tail and won't introduce any clicking like a normal true bypass. You still have the regular bypass switch to go into true bypass between songs.
Again with the toggle set to In Level, you can also set up an infinite decay time by maxing the top three knobs, and then use the Exp stomp to let sound into the reverb, building up a pad/soundscape kinda thing, and then hit Exp again and play over the top of that without your new notes entering the reverb.