First, I wanted to thank all of the Effective Altruism Global organizers and participants. I found it to be very valuable and overall well put together. There was obviously a ton of work put into it, most by conference organizers who I don't believe will get that much credit for it, and I very much commend their work.
That said, there's always a lot of room for new ideas, and I find I often get a bunch of ideas at and after these conferences. Because of the EAGx events, ideas described now may be able to be put into action somewhat soon and experimented with.
As may be expected, I recommend that people make all of their ideas be independent comments, then upvote the ideas that they think would be the most useful.
I strongly suspect that the group photo is of very high value in getting people to go, making them feel good about having gone, and making others feel good about the conference. However, it sounds like trying to optimize to shave a few minutes off would be pretty high value.
I felt that the group photo was a waste of my time because I wasn't visible to the camera. But if I hadn't participated I suppose someone else might've gotten my bad spot.