I attended a few Bitcoin meet-ups in Hong Kong. It was a fairly international crowd from different countries (locals, expatriates living in Hong Kong and visitors) and conversations flowed easily.
As you just said, it was bonding over some pizza and wine (held at an Italian place). The vibe was very casual. My impression is, most people (myself included, as I moved very recently to the city), came to make friends and getting to know people, rather than nerding about Bitcoin. I mean, sure, Bitcoin was part of the conversation, but I suspect it soon drifted towards all sorts of things, like travelling, living etc.
Most of the crowd was relatively young (20-30), some were retired (60+), so, needless to say, the group self-segregated into age groups where they could have more common things to talk about.
Out of a crowd of about 25, there were also 6-7 girls. Even though it was obviously not a dating event, there was a tendency observed for subgroups to form around a girl as the centre, as it happens in many social events with skewed gender proportions.
It may sound off topic, but my impression is that many people living in urban areas crave for some company, after work, so the conversations flowed easily. It was a totally unstructured event, people just walked in, and started chatting with whoever stood/sat next. Nobody had to do any work to break the ice as such. Also, my event did not have any gatekeeping literally anyone with zero knowledge or interest about Bitcoin could join.
If someone is super introvert, and does not want a conversation, then they would rather stay home? So not like you, as the organiser, will have to do anything specific to encourage conversation. But if you notice someone is being a wallflower, go say hi, and welcome them, that should be enough to break the ice.
In general, try to have a set up where people can move around and mingle with different groups and participants, rather than a dinner table set up where you are mostly stuck with the person right next to you (and if they don't click, it becomes awkward).
Keep the first event unstructured, but try to find 3-4 persons who are genuine, smart and interested in carrying the group/meet up forward. Then you have a core team of organisers. Then, may be each week/month, you guys can raise a couple of interesting topics or present developments for someone to talk about for a few minutes. Keep one topic beginner friendly, like
setting up wallet
doing first lightning transfer
think in terms of Sats rather than Bitcoin as a unit of measure (which is important for the next point)
why the apparently high price does not mean one has missed the boat for life, and why he can and should still put his first $1000, as you can still get about 850 Sats for a dollar
to initiate new Bitcoiners.
Make another topic a bit more abstract and advanced like
talk about quantum resistance
whether treasury adoption and Strategy/Saylor contribute to market froth and bubble
core vs knots
fedimint protocol
But also, keep plenty of space and time for people to just talk (about anything) and mingle without a specific agenda, since that is always a big crowd puller.
Also, depends on your geography, but it always adds to the theme of the meet up if hosted at an establishment that encourages Bitcoin for payment. Particularly, if you are trying to low-key orange pill a total new comer, it is much easier to convince by saying that he can buy a pizza right then and there using bitcoin, instead of going to an exchange.
Peer to peer networking, and transactions. Specifically, I think if someone has Bitcoins, but needs cash (because...life happens) and others are hungry to acquire more, it is probably good to encourage a peer-to-peer trade at a midmarket price, rather than both going to coinbase and pay their spread.
Knowledge sharing, demonstrating how something (e.g. a wallet, transaction) works, or some software they themselves developed. Who knows, some folks may come up with a billion dollar start up idea from these, as the eco-system is so young and still evolving
People whose entire agenda is selling some shit (insurance, credit card, a used car or whatever) or people who quickly take the conversation in a direction where, in some form, they are very keen for you to invest in something
Thank you for taking the time to go into specifics and acknowledge pieces of the puzzle. I am going to pull different parts and apply them to the meetup and for future reference.
My Suggesion
Encourage
Discourage