If maps and menus are your thing, you could do worse than checking out Europa Universalis 4—something you can do this weekend for absolutely no money at all.
It's a Paradox grand strategy game, and so all but guaranteed to be unlearnable in a single weekend. Nevertheless, if you think you're up to the task, you can head hereto download the Steam temporary trial version. If nothing else, you should have time to conquer a few of the smaller nations. If you like what you play, the base game is currently 75% off.
For current owners, new expansion opportunities arrive in the form of the now released El Dorado DLC. The add-on's focus is on Central and South America, and it also features a nation designer that'll let you custom create your own empire.