As the people like to say, quoted for truth. When you have played the game with various chars on various difficulties and got a significant amount of knowledge of the game, you may start feeling a little short-changed, since you're playing the same thing over and over. What saves the game, makes it much better and more fun (rather than repetitive, since you can play with the same lineup 5-6 times and get the same result) is setting some parameters, checking out various tactics, various lineups, and various tricks.
For people who just started playing, as Zechno said, that may seem intimidating. I can only advise them to play the game for fun, the way they feel like playing it and reap their own rewards. This game is not a contest with big prizes for winners and the best players out there - so everyone should find their own means of getting as much fun as they can from it.
__________________
|