If we do domination - which I voted for - maybe highest score should be used for victory as opposed to earliest date/fastest victory. Highest score dom would require different strategies and offer a change of pace for the SGOTM.
If it will be a Domination game, then I believe that this idea has a lot of merit.
The precedent, of course, are the Score-based Medals in the XOTM competitions. As a player who struggles to get the rare Score-based Medal (which are different from the Fastest Finish Awards), I would love to read about strategies that people use to get really high scores.
That said, I think that we're ready for a change of pace... a Culture-only Victory Condition would make for a fun challenge. Indeed, such a game might help us finally get some good statistics on Sid's vs stop-teching-early Cultural approaches to help in determining which is better.
We might see the most variety in approaches in a Continents (i.e. Astronomy-required) Conquest game, which I'd also be up for playing.
Actually, I think that a Continents Conquest could go hand-in-hand with a Cultural game, such that you wouldn't have to have Cultural Victory as the only option but it would be far more competitive of an option than in SGOTM 11. As long as all of the Religion-loving AIs aren't starting on other continents, Cultural games could reasonably compete, while those who got unlucky with Religions could still finish with a Conquest win.
You'd also then have the balance between taking over your continent early versus beelining techs to be able to go after the overseas AIs.
Vassals kind of unbalance Conquest games, though, in that those who tech the fastest can take advantage of cascading Capitulations for a relatively easy win, so I would propose turning off Vassals... then we'd probably have a lot more competitive results out of the Cultural games.
Throw in Raging Barbs to give the Cultural games a reason to build a few Military Units, while the most successful-starting Conquest games (wiping out all of the neighbours early on) would then have to face a new enemy before being able to sail overseas--the Barbs!