@Kingreno: While following both your and Skyfish's spoiler it soon became very aware to me that something was wrong. I never expected that the game would advance as it did (both of you got far more land than I expected). So I stopped checking things outside your immediate range. As it turns out this was a mistake and so far it appears to be the only biggie, which makes it even worse for me. Sorry for the unbalancing situation
EDIT: I see that I even made a huge mistake (regarding luxuries) on the original landmasses