every one I've ever played seems like excel with a GUI This is true, but the art of strategy game design is in bolting the right interface to the right spreads

every one I've ever played seems like excel with a GUI This is true, but the art of strategy game design is in bolting the right interface to the right spreadsheet so that the people will actually enjoy applying themselves to the problem. Relatively few people find the math inherently fun. The better games lend weight to judgement with layers of complexity, competing demands, random elements, and multiple victory conditions. On higher difficulty levels, the Civilization games actually cheat, which means by that point not only do you have to be an expert optimizer, you also have to have very good judgement in order to win. And when that becomes stale, there's always other humans. In the meantime the game is dealing out rewards not only of military victory, but also the joy of "gardening": tending to your cities, your bases, your whatever. This is a big part of the gulf between turn-based and real-time strategy games. Turn-based games can take weeks or even months to play through, which changes the kind of thought you're able to apply to each move and amplifies the reward of seeing your empire grow, while real-time strategy games tend to favor entering a match with a pre-determined strategy and implementing it efficiently. In my experience, people tend to have a strong preference one way or the other, not because the core game is so different, but because they find different things rewarding. In that sense most strategy games are variations on a theme rather than truly unique. Compare correspondence chess and speed chess to OTB chess--the game is the same, but the experience of playing them is quite different.