Undeveloped response for item 4.
To my knowledge people form close bonds in two ways. First: sharing things which make them feel vulnerable. Those things you feel as though you need to trust someone a lot before you can tell them. Paradoxically, telling people these things creates trust in them and encourages friendship. Just don't give too much too quickly. Plan: create exercises where people are directed in sharing intimate things about themselves, perform these at meetups.
Second: Jointly overcoming adversity or challenge. When a new member joins a meetup, take them to do things you are good at and help them become good at it too. Then switch roles.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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