I've never heard the term revolving credit referenced in our credit scores. In this case does it mean that you have a good limit on your credit cards, and consistently stay below it? Or are they referencing something similar to a line of credit, but not quite the same?
I'm Canadian too, with a credit score of 840. I have ONE credit card right now, no mortgage for the past 16 years, and never pay interest on anything. Mr. SP also has one credit card. His score is 830 (we have no idea why it's lower). We do have pretty high limits on our cards, but rarely use anywhere near those limits. What we spend on our cards sounds pretty similar to what you do. We are much older than you, but our credit scores have been this high for decades, so it can't just be the age thing.
I think most Canadian banks now let you run a credit score for free - it's usually somewhere on their home page or sign-in page. RBC does, anyway. Maybe you can run one and see if anything weird shows up.