First, I was only talking about AI, not about a AI and human.
Second, this would lead to the conclusion, that civs which need an active part of you are in general weaker than those with a passiv part. But thats not what we are aiming for, or?
A UA is only one part of a civ's kit, though. The other elements of Venice's kit are fairly 'passive' in the strategy sense of the word. Realistically, though, Venice is such a strong exception to the rules of civ that I don't even feel that a comparison with other civs is worthwhile.
G