Ask HN: How would you design a better Meetup?

I love the idea of Meetup but find the execution to be really lacking and there doesn't seem to be any alternatives. On the organizer side, you set capacity and there's no penalty to RSVP on attendee side even if you aren't going to go, so good Meetups fill up really quickly even though maybe 1/3 of the people who actually RSVP end up going.

Organizers are hacking Eventbrite to do paid events on top of Meetup (confusing), messaging is really clunky, email notifications for each individual meetup fill up my inbox, search/discovery is terrible (digging through abandoned meetups, low attended meetups, etc.)

Are there alternatives? Is there opportunity to build something better?