I would start with this: If you buy into the diagnostic that there's a growing dependency on consultants, then you should be investing in the training of public servants, especially middle and senior managers.
Just anecdotally, way back when I was an assistant deputy minister, I went to MIT. I took the four-day course on IT for non-IT managers. It helped me for quite a while. There are project management skills, risk management skills and all sorts of things.
I would...just as a benchmark, whatever that number is the government is spending on training and leadership development—the PBO could help you benchmark it—double it.