When I travel back and forth between Revit versions, say between 12 and 13, I find myself missing things. For example I wanted to see (in 2012) how many views were assigned to view templates and which ones were really being used. In 2013 we can add that parameter to a View List, 2012 not so much. In 2013 we can select a view template and see how many views are assigned to it, in 2012...you get the idea. I wish life and project conditions didn't make it hard to "just upgrade". Just do it, as soon as you can!