As I am not a Canadian, I am not sure that I have the right to comment on this issue. However, I would argue that the government should acknowledge that the execution of Riel was a mistake but it should probably not go so far as to name him a national hero and a father of the Confederation.
It seems clear that the Canadian government overreacted when it executed Louis Riel. It is certainly possible to argue that Riel was fighting not to overthrow Canada, but rather to protect the Metis people. His uprising was clearly never an existential threat to Canada. It does not seem right to execute a man for treason when he is trying to uphold the rights of his people.
However, it is clear that, at least in the Northwest Uprising of 1885, Riel was consciously taking up arms against his own government. By this time, Manitoba was a province and had accepted Canadian government. It is clear that the Metis and others had real grievances rising from the way in which they were being treated by the Canadian government. However, the proper way to handle grievances in a democratic society is not to take up arms. Someone who is willing to fight against his own government probably should not be seen as a hero of the nation.
Thus, I would argue that Riel should be respected as a fighter for Metis rights. I believe that he should not be seen as a traitor. However, what he did seems to me to disqualify him from being seen as a true hero.