I see... Well, I always felt corruption ruined the game because you could only ever have two groups of six or seven cities that were useful (production wise). Without corruption you can (for instance) play on a map of the world as a European nation, leave the Aztecs, Yanks, and Iroquois out of the game, then have a big race to colonise the unihabited Americas.
Of course you can still do this with corruption on 100%, but you can have a huge industrial base on another continent without corruption.
If you like a little corruption, robehans, go ahead and bump it up a bit. Thanks for the feedback.