Also, speaking of the Megaman issue, this could be something that lends itself better to episodic content? Using not only player choice for shaping the story, but also combat tendencies and oft-used player strategies, adjusting enemies' tactics accordingly?
Episodic content does indeed allow improved iteration based on consumer feedback (since it actually exists.... haha)
It is difficult, I wouldn't dream of saying otherwise. It basically requires the combat team to be as good as the most veteran player will be after a few months of playing the game before the combat system is even fully operationalized (or require going "back to the drawing board" a number of times after a combat system has been finished). With a game like Monopoly, it is easy (relatively) to devise an AI that plays smart. After all, Monopoly has been out for nearly 100 years. You all will have to devise a system that requires experienced players to think on the fly, while not completely scaring and penalizng novice players who just want to be able to one-hit everything to more on through the story.
There's an aspect of simply knowing the rules, but there's a bit more to it than that. With monopoly, only one player moves at a time. That makes a gigantic difference (I actually worked on the
ORTS Research Project at my university one summer and this was cemented home. I assisted with improving 2D pathfinding algorithms as well as combat mechanics for target prioritization between opposing squads).
So a good player can determine a particular sequence against a particular enemies, but the biggest thing is that the player is adaptable. If you know Storm of the Century is amazing, and while you're setting it up you realize the AI is threatening you in some other way, you can abort and shift to a different strategy. However, depending on the circumstances, you may NOT change your strategy.
The adaptability due to real time changes in the environment is a large part of what makes it so difficult. Which is why a difficulty level that is basically "use abilities" or "don't use abilities" is much easier to do as it's binary.