Allow creation of new entries in Many to One custom table

I love the custom table functionality, but there seems to be no way to add a new entry from the feature itself. I have to go to the custom table and add a row that way. It would be much nicer if I could just add a new record via the selection box in the feature (similar to an editable choice list).

This would allow me to create it right from the Feature, then use the 'link' on the right to pull up the record and fill in the other fields.