Hi there,
A very useful feature to have would be the possibility to setup a channel delay time for the left and right channel of the main outputs.
When using a stereo cabinet or recording into a DAW, it is very useful to delay one of the channels (left or right) a little bit, let's say 10 milliseconds.
This makes the sound really fat - sounding like two guitars playing simultaneously.
I used this feature with my Boss GT10 which offers to set up the channel delay time for each preset.
In case you consider this feature, I recommend to make it rig specific.
See the setup display of my Boss GT10 as a reference in the attachment.
Cheers
Michael