Changing hat, as they say in British English, to sound design, I feel there are some enhancements ETC could incorporate in the AV console to make it more attractive to amateur dramatics. In a typical stage setup with a speaker each side of the stage it would be useful to pan a mono effect to match its implied position on or off stage, e.g. radios, telephones, doorbells etc.
It would be even better if processor power allows, to provide some simple audio processing: bass cut to simulate an on-stage radio or record player; squawky band pass for telephones or intercoms; treble loss for off-stage sounds and if possible some reverb choices to give distance.
To keep the interface simple it would suffice in most instances to have a limited choice of processing effects rather than try to emulate full sound mixer variables, but they could add one, or possibly two, new dimensions to off-the-shelf sound effects which could be applied on the spot rather than the audio file having to be off loaded, processed using Audacity or the like and then reloaded.