Blitzkrieg was specifically designed as an even match between hypothetical armies of fictional countries "Great Blue" and "Big Red." That's fine, but it's also artificial. Wargames that depict historical battles invariably put players in situations that may or may not be "fair" contests. Incumbent on the designer, then, is to set victory conditions and other factors in such a way as to give each player a reasonable expectation of victory by superior play.
The Lost World: Jurassic Park that seems almost ridiculously biased toward the dinosaurs. Okay, so it works as a parent-child game, with parent as humans and child as dinosaurs. Otherwise, it becomes necessary to reduce the number of dinosaurs or the number of humans that need to escape (or both) to make the game interesting. But at least the game is adjustable.
Axis and Allies: Pacific is irreparably imbalanced in favor of the Japanese. My good friend Grant G. is brilliant at getting to the heart of a game, and in two or three plays, he seemed to have ripped the heart right out of A&A:P by developing what seems to be a near-guaranteed strategy as the Japanese player. Our group pretty much stopped playing that game altogether as a result. But in doing a little research for this post, I found that this perception is common among people new to the game. On boardgamegeek, Moshe C. has posted a detailed review that makes a fascinating case for the balance of A&A:P, so much so that I'm curious to go back and re-examine the Allied position for a way to beat Grant and restore order to the historical universe.
So where does all this leave me as a game designer? I think I'm even more sensitive to the importance of play-testing a game based on a historical setting that wasn't balanced to begin with, in the interest of making sure that no player can gain a guaranteed upper hand by following a certain path. It becomes important to ensure that there is no "saddle point" in the game conditions that causes every play of game to resolve to the same end-state.