When I'm trying to figure out what idea to use when creating things like narratives for music videos and short films I will have different mood boards with my base idea and then decide which one will be the easiest, which the harder, which the most fun, cheapest, time consuming, etc... (I don't normally have that many options to choose from, but you get the idea).
I will then go through a process of figuring out which one I can fit in my time frame, and if I can afford/get permission to use the locations and such that I would need.
But mood boards are definably the way to do it! I've got a pin board which I can do all sorts of string mood boards.. never done one but this thread had just given me the idea to do this!