The all three of the settings in the Map Extent Options from ArcMap need to be ported to ArcGIS Pro. The three settings I am talking about are:
1. Only show classes that are visible in the current map extent
2. Show feature count
3. Use current index feature as the map extent (data driven pages)
These missing settings are one of the main reasons why I have not been able to move many of my workflows to ArcGIS Pro.