The thing that's so great with Civ IV is that it's perfectly possible to ignore many of these variables, without it affecting the overall gameplay too much. For example, if you don't like religion, espionage or corporations, you don't have to use it. You can still win the game. But, when you've conquered the world with axemen and catapults a few times, or when you've done the cottages spam over and over again, it might be interesting to try something new.
You can make gold by spreading your religions. Or you can try focusing on trade routes and improve them with Temple of Artimis, Great Lighthouse, Custom Houses and Free Market. Or simply run a SE.
If you want to build units, you may want to have a lot of mines. But, you can also adapt Slavery and focus on farms instead. Or use your workers to chop trees.
And the absolute proof of how good the game is... is in fact the complains. Have you heard these before?
- Civ IV was too easy, all you did was whipping Axemen
- Religion was OP, all you had to do was to spam missionaries
- Cottages were OP, all you had to do was to spam cottages
- The Pyramids were OP, all you had to do was to spam specialists
- Corporations were OP, all you had to do was to spam executives
Well... These things sure are powerful. But, there is no way you can do all these things in the same game. On highter difficulty levels, it's almost impossible to combine an axemen rush with building the pyramids or spreading your religions. So when these people complained, they actually showed us in how many ways the game can be mastered. And that's the difference.
Well put! I couldn't have said it better myself!
