In my view, ATC is necessary, there fore they should be a government department. Funded by the taxpayer for the taxpayers benefit and responsible to the taxpayer, such as Customs.
It already is a government Dept. but the problem is, it is run just like a private sector corporation with an agenda to make money for its primary shareholder, ie the Government. They forgot about the "for the taxpayer" bit a long time ago.
Maximise profits, treat staff like crap, spend as little as possible to increase profits, look for further cost saving measures that also piss staff off and performance based bonus for managers that comply.
It would be interesting to hear from the older ATC's out there that worked for the Dept. of Civil Aviation and whether it was a better organisation with respect to service provided (Not airspace structure).
Most out there are still missing the point at the moment. Radar, ADS-B, whatever, serves no purpose at all when there is no one to monitor/separate/disable alarms etc.