Just to clarify some things:
I think that for a first edition of a G’MIC workshop, it could be convenient to :
- have the workshop entirely “online”. We have BBB instances here at the University that could be used to host the workshop without much limitations on the number of attendees.
- ask each speaker to pre-record a video of its talk, that would be then streamed. I think that it is specially interesting for people wanting to demonstrate stuffs, because it reduces the risk of things not working live
(also better for people that may be stressed to present live).
- On the workshop day, have the speaker connected online for answering questions after the talk, if possible (but that’s not mandatory, if the speaker’s schedule does not permit it). Here again, if the speaker is present, that’s better, but if he’s not available, at least we still have his video.
This is basically how LGM’2021 worked last year, and I actually found the format really nice, because we had time to prepare and record the talk, with no stress, and this was very flexible at the end
(e.g. I was not there for the questions, but @patdavid accepted to replace me for this task).
Having the time to prepare a video talk reduces the stress doing it live, and make it easier for the organizers to set up a reasonable schedule (because we know by advance how long each talk will last, and the chances something goes wrong are highly reduced).
Concerning a possible date for the workshop, there are no constraints yet. Doing it at the end of the year would be nice.
At this point, to organize such a workshop, all we’d need to know is :
- Who would like to be a speaker, and on which topic? Like we need a title of a talk, and a brief summary (a few lines). For example, a speaker would commit to making a video between 15 and 45 minutes.
If we get enough speakers, then we could agree on a date, et voilà ! 
Then, collecting the videos and setting up a schedule should be easy.