I've mentioned it before, but repeating it might not be a bad idea.
Consider writing up one of your ancestors or families you've "finished" or think you are reasonably close to finishing. Write it and explain your reasoning and methodology. I virtually guarantee you that in the writing you will notice something you neglected to do, an assumption that you think now might not be correct, or an error in your reasoning.
And if you don't, then get it published!
Since I've been writing Casefile Clues I have really noticed a few things of this kind in my own research and it's forced me to pick up the loose ends, organize, etc. Even if you have no intention of publishing, putting it together as if you are can be a very good thing.