But for now, and as far into the future as I can see, the floating exchange rate is the best choice for Canada given the degree of integration of the Canadian and U.S. markets for goods and services and labour.
The question can then be asked: “would further integration of Canadian and U.S. markets change this assessment?” The fact that the structures of the Canadian and U.S. economies are so different argues against using the same currency. But this could conceivably be overcome if there was much greater integration of all markets between Canada and the United States.