The ACC's expansion necessitated divisions so that the conference could hold an Championship Game. At the time, they did their best to divide the teams to meet as many needs as possible and balance the power. Balancing teams based on their strengths in 2004 was dumb and shortsighted. Powers ebb and flow. Then you throw in the new teams and the Maryland departure and you have an even more random collection of teams that have no real connection.
As I've said and written before, the two divisions should revert back to some sort of shared history. The former Big East teams (Boston College, Louisville, Miami, Pitt, Syracuse and Virginia Tech) plus one sacrificial lamb should make up one division. The other would be filled by the more traditional ACC teams. That makes sense historically, geographically, and probably recruiting wise too. And best of all, BC would play Miami every year! ("...caught by Boston College! It's a touchdown!")
It won't happen. The politics are too messy. But that doesn't mean it shouldn't.