@drmikepj Since you mention poster sessions, a few suggestions from my own experience of such events:
Allow posters to be on display for the entire duration of the conference, so people can read them at the time they choose. Some prefer more quiet times than the poster session itself.
Don't be greedy trying to pack as many posters as possible in the poster room, or the poster session will end up crowded, noisy, and difficult to navigate for everyone. If the room is full of posters, have at least two sessions and enforce that only half the presenters are there in each session (easy enough with odd/even poster numbers).