Dean and head of school positions should jettison their administrative responsibilities, instead operating as board positions. This would free those academics to teach and conduct research in a way that they currently cannot. School and faculty managers should take over many of the administrative responsibilities academics currently have, creating a similar splitting up of responsibilities as occurs between the chairman of a board and the company's chief executive.
With any luck increased responsibilities for such professional administrators would increase the talent pool prepared to embark on such a career.
A lot more work would need to be done to make such a change of management viable. But it is a worthy restructure to consider.