I believe right now, the event venue/address is limited to the ArcGIS Online locator. It's also being helpful by automatically geolocating the event based on the address. However, it'd be useful if we could edit the primary venue name and change the pinpoint to a more precise location.
For example, an event is held at our city hall in a specific meeting room. The locator map places a pin correctly on the street, but the meeting room is half a block into our city hall complex. Moreover, we're only able to enter the meeting room details in "Address 2" which doesn't appear on the Upcoming Events card, only when you click for event details. We'd like the option to list it as "City Hall - Meeting Room; Address" and to move the map pin to a more precise location.