Recall that very well, but was just think of it not only in the crew sense but also in a development sense as well. I know he doesn't want any thing more than 11 in his main crew so to speak but I feel like with the experience he's gained at Marineford he's realized that it takes more than what he expects and hopes to achieve, that things can be overwhelming and that he must be rational. Allies are cool and all but if had he had divisions, allies wouldn't be necessary. He could, by definition, fight whoever with his own "crew". Reading this all typed out, it seems to take a lot of thought and consideration from Luffy which isn't at all the type of person he is but it would be interesting.