Widgets as "fields" of another widget

When using a CARD widget (or future Form widget), it would be awesome if you could insert in SPECIFIC COLUMNS another card widget, or list of cards, or table widget.

The fact is that for related tables, sometimes you want the related table to appear in an order inside the record you are looking.

For example, I have a record of employees. I may want to have a section of their card with all information regarding courses they did. In that case, it makes sense to have a course table or card list in that order, not as a widget on the side or below, that stays blank when nothing is selected but occupies space.

So I scroll down the employee card, there is a section with his qualifications and below the courses he did, inline, so I can alter his qualifications if needed.

When in TABLE widget view, that other widget becomes like a button, opening a modal with that view.