Modifying system-generated add action

Since the only way to re-order the columns in a form view is to create a slice of the same table, it would be nice to be able to modify the system-generated “add” action to open the slice form instead of the base table form.

Though you can create your own “Add” action for the slice.

I need to be able to re-order the columns of a system-generated reference (owned by) form view. I’ve created the slice of the table with the columns in the order I want, but can’t seem to replace the form that is already referenced in. Any suggestions?

You need to create your own Form View and Detail View for that slice explicitly

Are you talking about when you click the New button on an inline view to create a new child record? If so, create a new VC in the parent table that uses a ref_rows() expression for the new slice, and hide the original. Then it should open the form view for that slice upon clicking new.