Hi Ben,
Sorry it isn’t clear how the Events Calendar PRO plugin and the Community Events add-on differ.
First off, Community Events will work with either the free The Events Calendar plugin or the premium Events Calendar PRO plugin. Just wanted to make sure that you understood that you are not required to install both.
The Events Calendar plugin (free) gives you the basic calendar functions that you would expect. A monthly grid, upcoming events, and single event information.
Events Calendar PRO (premium) gives you some additional calendar functions such as recurring events, map view, searching events in a location, week view, photo view, venue view, single day view, a calendar widget… I can go on, but you can find the complete list over at https://theeventscalendar.com/shop/wordpress-events-calendar-pro/
What the Community Events add-on brings is the ability for site users (not just site admins) to add events to the calendar from the front end. And of course the necessary settings to manage that kind of environment. You’ll have to have either The Events Calendar or Events Calendar PRO installed to take advantage of the Community Events add-on.
Does that help clear it up?
— Julie