The Beyond the Sword expansion has a diverse array of incredibly intricate and fantastic mods, but before I dug into them, I wanted to give the base game a chance, to refresh my memory about the specific changes made with the expansion. It was my intent to build my civilization around the new mechanics - espionage and corporations. Unfortunately, my starting position rendered that plan moot. I wound up uniting most of my continent under a single religious banner, with multiple defensive pacts ensuring that any major power in a position to threaten me was actually obligated to defend me instead. Spying on them would be hugely counterproductive.
What's more, due to the particulars of my geography, I am simply not generating the great people points necessary to found a corporation, nor do I have the surplus resources necessary to profit from it. (I have huge amounts of dye, but that doesn't trigger any of the corps).
Sigh. Maybe some other time. As it stands, I can't afford to waste any more time on the base game. I've still got nine mods I still want to sample, and though I can, of course, go past my 20 hour deadline, I'd rather not go too far past it. Civilization IV may be a great game, but it's only one of a hundred I have left to play.