I am defining UX for users to build an org structure that can be displayed as a tree

I am designing org tree editor and the user needs to be able to create org structure from the top down as well as from the bottom up - top down is straightforward but bottom up is trickier (see mocks)

What is the best way to handle selection in the event user doesn't want to roll everything up into parent unit - maybe they only want org units 3-5 to be rolled up into new org unit at top level maybe org tree editor is completely different view with more of a diagram / horizontal orientation?