Eric and Karen also bought us the board game Hansa. It's a buying and selling sort of game set in the 15th century Baltic cities. The primary challenge of the game never having enough resources to do everything I want to do. The rules are not really that hard, but they are a bit difficult to pick up. We spent our first game just getting used to the mechanics. I don't think my 7 year old could pick up this game.
The game itself is both fun and challenging, but it is short-term, since you can't do much to prepare for the future. And you can't even plan your next turn, since the board will probably change as the other players move.
Rating: good game.