I'm looking forward to the changes to diplo victory, but the 'economic victory' argument for the current system is a misnomer. A diplo victory in Civ V certainly involves economic favour - but then so did the diplo victories in previous civs if played diplomatically; you were just bribing other civs instead of city-states. And in neither case is it exclusive. Yes, you'll get some CS favour by buying the CSes - but chances are you'll get some early credit killing barbarians, gain incidental favour from GP, Wonder and Natural Wonder quests CSes offer - and yes, probably occasionally from capturing a CS one of the others wants you to destroy, but there's certainly no need to wipe them all out. Since there is almost always competition for CS favour with other civs, and sometimes warfare that will prevent you buying votes, you'll also likely be forced to earn votes through conquest at some stage.
This is, in fact, what I like about the diplo victory - it promotes more varied play than the other victory conditions, and will generally require a good mix of science, policies, money generation and conflict to pull off unless you just want to save cash until you can buy all the CSes at the very end of the game.
I agree that the diplomatic victory right now promotes more variation in how you play. When it comes down to science or culture you pretty much follow the same steps and with domination the differences in how you play are only marginal.
The expansion does add more factors in which one can win a diplomatic victory, one that counts more on espionage and cs missions instead of simply bribing them. Having a strong economy wont ensure a diplomatic win anymore. (It will most likely end up my favorite victory now.)
I would like to see this more though. I believe that adding a pure scientific CS would be nice to add a bit more variance in the science department. Though I don't believe we get that in this expansion. (Sadly.)
At the same time I believe that a religious victory would be nice as it involves the entire world.
(Disclaimer: Just another idea I'm throwing out there in the next paragraph.) In order to win you convert about 90% of the cities on the map to your religion and build a special religious wonder only available once you have reached a certain age in your capital. You can try to have it spread naturally, make it easier to spread using special units or fight religious wars to puppet/annex cities that will help you spread your religion or go on crusades with special units that only convert cities and don't puppet/annex them. These units would be bought with religion, can't take cities and when used won't give you warmonger.
- It's a victory that involves the entire world, pretty much like domination and diplomacy (culture and tech are pretty much victories that don't involve other civs that much).
- It's a victory that can be won in multiple ways, both through domination, crusades, simply boosting your religion enough by means of buildings and or city states, sending out emissaries or perhaps have diplomatic means.
- It's a victory that can be done in the beginning, just like domination. Yet unlike domination it gets harder the more time progresses.
Now I'm just brainstorming and throwing out ideas.
I mean, if it's done like this, surely some extra victory conditions would be nice?