I've JUST got my ModDuo and am REALLY enjoying exploring what it will do. But just to add to what's being said here about multiple controls from a single button - that was the biggest surprise so far, that it wasn't already possible. Is there a reason why it isn't?
I'm used to being able to assign multiple parameters to a single CC controller (so that I can use a volume pedal to control input volume, reverb saturation and delay feedback all at once, for example) - I could conceivably assign different CC controllers to the same pedal in my Softstep, turning each one off while programming the pedal board, so that I trick the Modduo into thinking that I'm using 4 pedals at once, but that seems like an awfully long-winded way to go about it, and would mean that I had to edit the softstep every time I wanted to set up an expression pedal with an effect in the Modduo...
The scenes idea is a nice one, but still seems to be a more complicated version of just being able to assign the same controller to multiple parameters. I've also found this to be an issue when using two instances of a mono effect to stereo-ize the effect (I'm using two of the tremolo pedals) and wanting to turn them off at the same time... So maybe it would be possible at some point in the future to just choose an option to have a pedal install twice with the controls linkable or unlinkable (so, for example, you could have the gain locked between the two, but vary the speed of the tremolo on the two sides...)
Back to tweaking and programming!