No. Instead your tourism must surpass the culture of every civ (seperately).
As for SPs, I'd stronlgy suggest to go tradition. Liberty can be useful, but for me the merchant from optics is usually enough. However, that being said: If the map setup is terrible and you find your capital to be placed in an inland sea or a cut-off part of the ocean, you will need a good city state or two to get those trade routes running.
I guess liberty might be the better option if you want to go for a science victory (and that is actually not that hard, considering that you will crank out a lot of beakers with your puppet cities).
Personally I stick to my tradition-super-wonder-city.
The problem I had with my current Venice game is that I fell enough behind in the tech tree the other civs can wonder spam before I even reach the technology to get to it.