Sunnyways Sunnyways:
the head of government should not be selecting a person who may have to rule against them. Perhaps there might be some way the PM could ‘consult’ on a candidate selected by parliament in secret ballots - a less formal version of the Israeli and German presidential voting systems - without having to get into constitutional change which is all but impossible?
The Head of Government is the leader of the party with the most seats in Parialment.
The Head of State is the Queen (or King) of Canada, and the viceroy who represents the Monarch is a choice made by the PM and approved by the Monarch.
There actually was a Supreme Court case back in April that set a decision that Canada does not have to proclaim whoever succeeds Queen Elizabeth as Monarch of Canada, and we could appoint someone outside the succession of other Commonwealth Countries.
But it still remains that person should absolutely be able and willing to rule against the government, should the government decide to change laws it disagrees with.