Most of the answers to ["What is a good opening on a 13x13 board"](http://boardgames.stackexchange.com/q/3486/1749) deal generally with the differences between large and medium boards. I'd like to ask more generally about how I should be thinking on a 13x13 board. I feel comfortable fighting on a 9x9 board, and generally on a 19x19 board I prefer to play for influence throughout the early game.

However, I get confused in the middle. With a medium-sized board the center is small, which suggests a more territorial style, yet due to that same smallness, a "moyo" including most of a side is easy to set up, which makes me want to that. How should I think about these differences in the fuseki?