I'm a big fan of FixIt Clinics, i.e. community repair workshops. Here's an example of one of their posters:

https://allevents.in/mattapan/fix-it-clinic/200026636930752

Here's what I like about it: it communicates. What, when, and where. And crucially, photos showing what the event looks like. Photos of real people fixing real things.

The author demonstrates that AI-generated posters can imitate many artistic styles besides the generic default, but these examples suffer the same problem as all template-based posters: they don't communicate what the event is actually like. What does a samba band performance look like? (There are drums, I guess?) What does a circus skills workshop look like? (There are juggling clubs, I guess?)

These posters may be more aesthetically pleasing but none of them make me interested in going to the event.