You can't restore CS that are puppet/annexed by Venice or Austria using their UA. They've forever lost their CS status and can never be liberated. I think it reduces the number of votes required for WL by 1 though, so it isn't as bad as you think.
And on deity, if you don't take a city some AI won't even settle for peace. Even if you slaughter their units, they just keep pumping more and it doesn't account for the fact that they're losing units and still wont settle for peace.
Tell me pls what is the last official patch?
Do you have another city on the coast ? Are there sea ressources ? How good is the mountain spot etc.
You can get approximately the same amount of science through a good food location if you get approximately 25% more pop compared to an observatory. That's the rule of thumb I use. And less happiness, more gold more production as a result.
What's the consensus for how the latest patch changed things in single player? My standard 4 city tradition on deity now seems more challenging. I just can't expand like as quick as I used to.