One of those mistakes I’ve made plenty of times myself.
There are groups out there who have been playing campaigns for decades. They get together when they can and go on one more dungeon raid, where they pretty routinely move from room to room, emptying them from threats that just sit there, waiting for them.
My mistakes have been in the completely other direction.
Mark Rosewater is the head designer of Magic. That game has thrived for well over 20 years, with a number of players exceeding 20 million. For comparison, D&D has about five million players, and has had around 20 million people playing it at some point during its almost 40 year history.
So, Magic is big. One key to its continued success is the willingness to reinvent itself. From the point of view of a typical competitive player, its a new game two or four times a year. For the more casual crowd, it can be even more or less. Magic shouldn’t even be regarded as a game. Its more like a framework on which you can easily design games on…. which makes it actually pretty close to most RPGs in that sense.
Of course, the game doesn’t completely change. Many of the basics are more or less constant (many of the basic assumptions are played around with in different sets). However, this is actually the key. The design team always tries to find a way to twiddle with the game in order to keep it familiar (I had a thirteen year hiatus and no problems coming back), but at the same time, to keep people interested, they bring new ideas and concepts into the sets.
This is a pretty basic concept in all arts, actually. Sure, there are always people who are ahead of their curve and will be seen as visionaries sometime in the future, when the rest of the world is finally caught up. However, they’ve missed a key part of the equation. You have to build on what’s already there. There is a limit on what you can do.
Now, of course, this isn’t quite this simple. I watch and enjoy a lot of fucked up movies. I’ve seen over two thirds of the movies on 366WeirdMovies.com and I would have seen the rest if they weren’t so hard to find. I seek out this stuff, but I’m in the minority. On the other hand, there are also plenty of people, who are willing to look at straight-to-video action movies or Adam Sandler comedies as their form of entertainment.
However, these are the tail ends of the Bell curve. Most people are in the middle. They want something new, but at the same time, it should be firmly built on what they already know.
So, the key here is to know the players, but to be on the safe side you should try to stay within a throwing distance of something familiar. You should reserve your stranger ideas to people you know can handle it. Unless you know how to ease people into these things like the best stand-up comedians.
At the same time, do push the limits. Or better yet, encourage your players to push their limits. Don’t repeat yourself too much either.