The original Starcraft was one of the most balanced Real Time Strategy games I've ever played. Three unique races, a multitude of different strategies required for victory, Blizzard created a masterpiece back in 1998. It's a game I still occasionally pull out and play at LANs.
Starcraft II looks to be fantastic so far, it's my most anticipated game of 2009. Blizzard may make games that try to aim at as wide an audience as possible, but it's hard to deny the effort they put into making a highly-polished and replayable game.