Add Divider Row in Kanban View

In Kanban view, I can select which columns to show up. I’d like to be able to insert a pseudo-column that is really just a movable divider row. See attached mockup.

DividerMockup

In a perfect world it would behave identically to the column rows. Just inherit the column of the outside Kanban wrapper. Only difference is that it would need to be sortable so I can choose where to insert it.

Alternatively, if I could just set the background column on the rows. Then I could make one act as a divider.