The Borg seldom does things by halves and we'd be surprised if this is the only shot in its locker.
You have not idea what you are talking about. Just the opposite. Making the Borg commit resources properly to anything is utterly impossible because there will always be at least two BUs whose interests will be threatened and they will throw spanners in the works.
Disclaimer - I once upon a time was a Borg unit so this is an insider view. Most implants have been removed now..