Let's be honest with ourselves here. At some point in time you're going to have problems coming up with something to do in your game. This doesn't mean it's the end of the game, just that it is likely to be a boring session unless either you manage to power through and come up with something, or your players really knock it out of the park for you. This has been a problem I've had with my L5R game for a bit, though not as totally as the topic suggests, and I figured it might be a good idea to both get my thoughts down on paper, and share some of what I have learned.
You Can't Do That!
Some of the ideas you have when you're stuck like this are very drastic. Some of them are down right shocking. The problem with them isn't that they wouldn't get things going, but that they have a chance to be irrevocably setting changing and you may or may not want that. For example, it would be a bad idea to burn down half of a city in the middle of winter, however fun it would be, because that one act would dominate the rest of the game for some time and you may not want that. The same is true for the classic "reach out and kill someone" plotlines and many other similar things.
On the other hand, some of the things you want to do are going to be too close to something you've already done. You don't want to repeat plot lines, not very close together at the very least.
These two together tells you the first thing you want to know: don't jump at the first idea you get. Give it your attention, work with it, but make sure it does what you want it to do on the big scale and not just the small.
The Question Is 'Will' Not 'Can'
One of the big issues I have with my L5R game is that two of my players are quite high up on the social ladder on the official side, and two of them are fairly high up on the unofficial side (one has overlap, so 3/5 pcs are "mover and shaker" types.) This can heavily restrict the kind of challenges you can face the character with simply because so many common problems have such mundane solutions for them it is ridiculous. For example, giving a character an errand to complete isn't much use when he can delegate the errand to one of 70 people - and would normally be expected to perform that delegation.
However, the problems that come up from high levels of power are so often focused on the question of "can" - as in "can he do this?" - when you really want to focus on "will." With the focus on 'will' you can bring up deep challenges for the player by focusing on the more emotional and dramatic side of things. Will the high ranked political figure take the bait when insulted? Will he let an even higher positioned person do things that he disagrees with? It can make for some very interesting, and deeply personal, stories.
Some Responsibility For the Players
While less an isue for planning the session, you do have to accept that the players do have some responsibility for the game themselves. If you present them with potential things to do and they turn and walk away from them then it is on them. If you ask them what they're doing that day, and they say they're going to go read a book and relax all day that is on them too. The point here is that you don't have to break your head trying to cover every possibile contingency to keep things going. Sometimes people just avoid excitement and adventure and that is ok. Just make sure you let them know that they are avoiding excitement and adventure.
A Bit of Fast Forward Never Hurt Anyone
The last thing I want to mention is this. Sometimes the trouble with coming up with stuff for a session is because we're waiting to get to a big event and stuff happening in between can be weird. When that is the case, remember that nothing is stoping you from skipping forward to that date. Let the big event happen, and then go on from there.
What do you do when you have trouble coming up with stuff for game? What challenges do you find yourself leaning towards to start trying to shake things up? Sound off in the comments.