I have tried both methods, of Commons and Google docs and found them both really wanting. The Commons method is just too much of a pain (uploading multiple pages to Commons, editing it, pushing an update, then going in each course to accept the update). I was hopeful about the Google doc method but I don't think it is helpful if you want your page in Canvas to look a very specific way. (If anyone cares about the details, it's because embedding the page in a Canvas page can only embed a frame that students have to then scroll through. Even adjusting the height and width and margins of the frame, I couldn't get it to look very good (and it cut off the end). I could embed a link that students would have to open in another window but then they see the whole doc in Google docs and it doesn't look good that way either.)
So I really hope my university will allow the Canvas Blueprint courses as that seems like the only perfect solution. Thanks to everyone who took time to suggest solutions!