The Club version, does have a few more features. Enhanced SEF, enhanced crawler functions etc. It won't include any fixes over 2.0.11 as this is stable.
JEvents RSVP Pro, is the event registration system which has a massive feature base.
By detailed events what do you mean? yes it allows you to post details of your events, as the current does. But you can get the custom fields plugin if you want specific fields when creating events etc.
Yes you can set it up for users can create events, Jevents has a built in Authorised User Mode, so you can limit it to users which allows for a stricter permission system.
Or you can use Joomla's own usergroup's to limit who can create events.
I hope this clarify your issues, should you have any questions just ask