Pulling connected records from separate tables

I'm leaning towards using a joined table, but there are some things you can do to make the "manual" part of it seem as if you are doing it all in one spot.

While in the same breath giving you the reporting and insights (no pun intended) to your data.

Have you experimented with an "editable" child table on the main interview form?  This would be your joined table, but you basically be a grid edit child list.  Makes it really easy to add multiple records at once.