As far as I know there is no way to have the native player board explorer tell you the target of factory continents.
Can this be added as a column in the continents pop up?
Additionally, it would be great if the territory could have a green ring or something around it on the map.
+1
Yep - you can see the 'members', but not the 'factory.' One potential problem with showing either or both (but especially the factories themselves) is when designers use off-board mechanics.
If it's off board then it's probably less important for players to know at least...