I think it's stronger with the extra couple of months and the CRA declaration.
But don't feel my opinion matters or is appropriate - only you know other aspects of your file and history and application, some of which might be relevant and important.
Generally applications for applicants out-of-status and only just over the minimum 12 months residing together to be considered common law are going to get more scrutiny (for obvious reasons).
Want to strengthen your app? Get married. This removes from the discussion whether the technical requirement of 12 months residing together is met, and all of the joint residence / cohabitation information becomes evidence in support of the relationship.
I know some don't wish to and you can have your own reasons, of course.