Now that we've got more experience behind us - and have acknowledged that in person won't be possible for months to come - here is info on what we've been doing.
1. and 2. For our March meeting, we used an audio-only format. For May - and planning for August - Zoom is our platform due to the size of the Board (21 members and five staff, not including presenters). We have a couple of members who access through audio-only for differing reasons; everyone else uses the video option. By late May, Zoom had rolled out their additional security features; prior to that we would not have been willing to use it.
3. For March, we cancelled Committee meetings; in May we went ahead as planned and used Microsoft Teams, as there are fewer participants.
Other info:
We have re-designed our board agendas to focus the discussion agenda on critical matters and use a "heavier consent agenda". The chair is very clear at the start of the meeting to ask whether any director wants to discuss any of the items in the consent agenda - somehow with more care than usual as we have put items in there that would normally be included in the discussion agenda. (The Chair always asks; must be something in the tone at these meetings that tries to force people to consider the question carefully.)
In the past, we have used GoToWebinar for virtual meetings when we have needed to share confidential/sensitive presentation slides that we didn't want to post to the board portal.
Our AGM was virtual in 2019 using GoToWebinar.