As far as my proposal is concerned, Ms. Turnbull and I may differ in one respect.
A prime minister always has the ability to request the prorogation of Parliament if he or she has the confidence of the House. If the prime minister no longer has the House's confidence, his or her advice is not binding on the governor general. Without amending constitutional acts or other legislation, you would have to establish a mechanism whereby the prime minister would be deemed to have lost the confidence of the House if he or she did not first obtain the House's consent. The governor general would not, in that case, be bound by the prime minister's advice.
Now the issue is finding the mechanism to do that. I propose including in the Standing Orders of the House of Commons—