If a game is a big hit, run a second season like a TV show. Axe it when it runs out of steam (like a TV show) – and bring it back for a reunion in 10 years with the original cast.
The only problem I have with short campaigns is keeping them short. I like to meander, I like to find out what happens to the characters. I dislike prep (too much like the planning I have to do for work) and I don’t plan ahead.
Here’s what I have learnt: