Beyond an exquisitely handled murder mystery, this is an exploration into Bruce Wayne's own psychoses and hypocrisy. Honestly, why would such an individualistic lone wolf need so many underlings? Take into account Bruce's age: he's in his mid-to-late-thirties by this point, as the story is set one decade since the Batman first appeared on the streets of Gotham. As protector of the city, Bruce Wayne has an overdeveloped paternal instinct, and has subliminally acquired a family under his alternate persona.
On the other hand, he tries to push this family away, because he feels his is the only soul tormented enough to sacrifice himself to the rigors of being the city's justiciar.