If you really want to be the fastest, it might be usually a dominate-based victory, whatever for DV, RV, CV or SV, in current base version.
The followings a a popular argument on Chinese forum (I thought there's a similar thing here), posted just after the game released. Unfortunately, they still seem to be true.
- For fast DV, you should take every enemy’s capital;
- For fast RV, you should eliminate most civs and leave them 1 capital, then found religion and sell several cities to them;
- For fast SV, you should eliminate most civs and leave them 1 capital, then gather the whole world’s power to launch rockets;
- For fast CV, you should conquest most civs and leave everyone 1 city as foreign tourism source; also you can eliminate some most cultured civs, which means who have the most domestic tourism, to win faster.
All of them above are some most extreme examples, but the base idea is similar, based on the speed of domination. It was very boring I think
.That is why Chinese forum turned to peaceful victories very early last year (of course, it will be a little slower). There are many fast, peaceful culture victory game reports in different styles, likes relic-style, theater-style, even wonder style. One different from science victories is that it should not be measured by turn number, for they have different opponents.