My advice is don't over think it. The biggest drawcard & reason for attending is meeting & talking to other Bitcoiner's.
I've found mid week after work hours seems most preferable to people.
You only need 1 other person to have a meet-up. Don't stress about finding new members, they will find you.
We have ours in a local public park & I grill up some meat on a portable charcoal BBQ.