Meetup organizers who are frustrated at the changes in the service may want to consider RSVPMaker as an alternative. With a WordPress website running RSVPMaker, you can be more in control of your own destiny by managing events on a website where you set the rules. By combining RSVPMaker with plugins and enhancements such as BuddyPress or discussion boards, you can round out the experience.
Version 1.2 will automatically retrieve profile details for a logged in user, and you can customize this function (see Changing the RSVP Form, Other Customizations).
If you try this approach, let me know how it works for you and what still needs to work better.
So interesting to run across this post! I recently set up a membership site for a colleague because Meetup had too many unfavorable changes. Glad to know there are many more unsatisfied users.