Why not add some complexity to this by having the player have to find all the diamonds and make sure the diamonds are of equal size, weight, and shape?

You can see how you might take a simple game and add complexity. But what's not evident in this example is that, just as there is a cost associated with adding complexity, there is also a cost to removing complexity from a game.

This is why the notion that a game is more "balanced" if all the variables have an equal affect on game play is so often criticized. The reason for this is that, in this view, "balanced" implies a game in which all variables have equal weight, and that, to be good at a game, you have to be able to recognize which variable is the "swing factor."

And the problem is that, even without taking into account the concept of asymmetry, this is not the way the world works. When you walk into a room, your eyes and ears have to do a ton of work, but your ability to walk has very little to do with your ability to navigate that room. You can have the body of an Olympic athlete, but you might not have the eyesight of someone who played a lot of basketball growing up.

So if we consider the different factors