You analysis of the size of vessels that can sail on the Great Lakes is excellent. There may be more traffic there, of course, but the vessels are of equivalent size.
The question you ask is difficult to answer in a few seconds.
In actual fact, the Great Lakes certification system is the result of an anomaly: on the Great Lakes, Canadian officers on Canadian vessels were exempted from pilotage because of a previous system.
In 2010, that system was deemed to be illegal. It did not comply with the Pilotage Act. It was transformed into a certification system in which those who were exempt took advantage of a grandfather clause and were given pilot certificates. Since the new Great Lakes system has been in effect, only about 10 to 15 Canadian officers have been certified as pilots.
So I have some reservations about exporting the Great Lakes model all over Canada and making it the common denominator of the certification system.