The only problem (and it's not really a problem) with PSK or any digital mode and SOTA is that these modes are not on the air regularly. The scarcity makes people wonder whether it's worth the effort to try if there's no regular audience. At one point many people had never worked any kind of S2S QSO across the Atlantic mainly because they were not on a summit the same time people the other side of the Atlantic were also on a summit. This was fixed by giving everyone plenty of notice and arranging a window when it was possible for both NA and EU stations to be on the air. It worked exceptionally well, there were plenty of stations active at the same time and many people got their first S2S across the pond.
So the way to solve the problem of not being sure if trying digital modes is worthwhile is to ensure there will be plenty of activators on the air and plenty of chasers to chase them. We need to do the same as the S2S event, pick a date and time window when the idea is to try digital modes. If enough people are prepared to give it a try then there should be plenty of signals to work. We just need enough people to QRV at the same time.
I could suggest a date, but this is as much your reflector as the MT's . Someone suggest a date, with enough warning so we can ensure we have our cables and software sorted and we can see if there is enough interest to have a digital day. You never know, it could be something that garners sufficient following to be an event that is held regular during the year.