Generally, L5R works less well as a sandbox game. It does much better when you define a range for characters, and give them a goal.

Our current game, for example, is set in 1122ish, and only allows Crab, Crane, Scorpion and Three-man Alliance. It centers around some events in the Shinomen Mori and the destruction of the Hare clan.... and every allowed clan has some stake in the immediate outcomes of the events.