Anyway, to each his/her own. IMO, turning off victory types other than Dom is a "terrible idea" -- you're basically making some AI play with one hand tied behind their back, because their leader-specific programming demotes them to a victory option they might not be best suited for.
Sure, lots of space between AI means slower land attack, especially when you're winning with pre-industrial units. I don't know what other "metric" is disadvantaged. Takes longer to establish trade routes? Yeah, but not a serious impediment unless you have a tightly wound strategy for early victory.
You can always add a few more CS to replace the AI you cut out of the Large map.