The thing is if you are Common Law (living together and all) you can collect more evidence that if you lived apart and then married (like me). You could have pics taken all the time, leases, joint credit cards, bills... etc. My husband and I didnt have any of that. What I would do if I were you is to periodically send evidence. You, every couple of months send a letter from ppl who know you.. or more pics... I was thinking of doing that, of pics of these holidays...etc. Why not do that?
The thing is...getting married is such a HUGE responsibility legally and socially as well, that is a time where there are sooo many fraud couples... maybe the marriage helps a little more?
One thing I know, our application was very very Candid. I didn't write it as a cold, to the point professional thing. I pour my heart out and at times I was funny. Like I am usually am. I was even argumentative in a way as well. I kind of tackled it as a university essay. It paid off, I guess.