I haven't bought the expansion yet, typically I only ever buy the Vanilla game and never get the follow on packs. I tend to enjoy the core experience and tweaking around with that better than spending $30 for spies I never use and a few extra civ's to play.
G&K has me interested though, seems a bit more in depth than just adding spies and lawyers.
What are the key good points and bad points? I've read the back of the box review that says what they were going for but I'd like to know if it was successful or not really and gather some opinions before deciding whether or not it's worth my money.. heh.
My take:
Overall it's a better game
Social Policies: Vanilla was always go Liberty First; G&K changes is now always go Tradition first.
The Freedom being a really popular policy compared to both Order & Autocracy due to being available earlier was addressed, but in the opposite direction of what players would prefer. (They delayed when you can open Freedom instead of moving the opening of the other two up)
Victories: Diplomatic victory considerably faster in G&K than Vanilla (you can be-line techs again going for Diplomatic which a patch to vanilla had eliminated)
Cultural also looks a bit easier while a few more techs required for science.
Specific tactics nerfed:
RAs heavilly nerfed with the DOF requirements on top of merely producing beakers instead of free tech.
Nerf bat also also to use Great Scientists to be-line. (It's now 8 turns of science with carry over instead of a free tech of your choosing)
Nerf bat applies to Great Person induced Golden Ages: Now just Artists
Nerf bat applied to PT (delayed)
Old functionality of the HS moved eras later. (HS is still a good wonder in G&K, it provides a Great Phophet now)
The religious aspects: are fun although the policies themselves are not balanced; you could argue that the balancing aspect is how much of a priority to make religions, but the AI isn't that good at choosing the best policies available for them.
Spy aspects: If you have a tech lead, you need to invest in spy buildings in your core cities to limit your loses. But if your behind, you can use them to narrow the gap.
City state quests: Much improved.
AI being so bad at managing happiness it needs the Chieftain bonus: Not changed in base game. There are however mods in both vanilla and G&K that address it. (VEM & GEM)