The Vatican should be a city state. Seriously.
As for whole Civs, I personally don't want obscure nations. While I'm not trying to diminish the impact that they've had on history, how can be really justify a civ like the Minoans (for example)? What would their UU be, a Minotaur? Civs that only exist through ancient archaeology and didn't rule more than the single island of Crete don't justify spots along side such history-spanning entities like the Ottomans, the Roman Empire, or China. Isn't Crete a possible Greek city name anyhow? If an ancient Civ was somewhat of a "forerunner" to a major Civ, they deserve a city name and a mention in the Civilopedia.
The major Civs that deserve spots (imo) are Celts, Zulu, Mayans, Italy, Israel, Korea, and maybe Vietnam (I could see it working if they used one of the ancient kings ruling an up-to-date Vietnam, kind of like China).
See, personally I disagree entirely. I like the idea of seeing what would have happened if the Inuit seized the opportunity to expand as players on the historical stage. A big part of the charm of Civ to me is the what-if - what if that interesting group had managed to become a major empire?
I am personally hoping for a non-western, non-military civ next. Korea would work for that. I also want more African representation, preferably the Zulu and an important central African/jungle group.