Currently you can only create a public event, or make an event private through the use of a private group.
We're looking into using the Events module for our various events throughout the year. Some of these events are for our super users only. Our super users have a specific user role. They also have a private space on the community, but we use a subcategory for that, and not a group.
So, I'd like the ability to also limit event visibility, and the option to register for one, based on a user role.
Edited to add: with the current this-or-that option, the Events module is really only usable for one type of Event that we we do, and not for the rest.
