Would be great for us if users could delete their own calendar events, but not those posted by others.

At present, you can set this, but its the ability to delete their own content as a whole, rather than just calendar entries. Thats done from their group

Groups/(Group)/Content/Deleting/Customize does seem to give this granular control. Thanks!

No problem at all. Enjoy

It's so often the case here that what one wants can be done, but can't be found...