Hey JimE2013!
Just to let you know, we did sent a loooot of pictures specially with our family, me during easter and few weddings with his family and of us while visiting my parents in Mexico, another thing we did was asking for letters to all our friends and family members writing or testifying that our relationship is genuine and know that we have been together for a long time, they dont have to be long, we sent a copy of our lease with both names, a letter from our neighbour also mentioning that he knows we have been living together for over a year.
We traveled together 2 times and sent them as well the copies of our e-tickes and hotel booking (we sent some pictures of the trip as well)
We also sent a copy of our joint bank account statement, since we mainly communicated via facetime, skpe or phone and we didnt kept any track of it.
I know asking letters might sound like a lot but both our families and friends are very supportive and they helped us, until now we havent have an interview or been asked for more proof.
Hope it helps and in this case it really comes to quality and not quantity!