How many and which ones do you think are missing, without considering new mechanics? (right now I remeber just the Mayans, Babylonians, Ethiopia and Portugal as some fairly requested but still missed)
The Civs that were in previous games but not this one are as follows:
Last seen in V: Assyria, Austria, Babylon, Byzantium, Carthage, Celts, Denmark, Ethiopia, Huns, Iroquois, Maya, Morocco, Polynesia, Portugal, Shoshone, Siam, Songhai, Venice
Last seen in IV: Holy Roman Empire, Native America, Vikings
Last seen in III: Hittites
Last seen in II: Sioux
I would
hope (but I guess I can't be certain after the last few pages) it's safe to say that there aren't many people who want Native America or the Holy Roman Empire to return. Unless they do something interesting with them (which is
possible but would probably require more work than they'd be willing to do), I doubt there's much interest in the Huns either. A number of these have been pretty clearly swapped out for others -- Vikings/Denmark into Norway, Carthage into Pheonicia, and Polynesia into the Maori. There's also a case to be made that Scotland replaces the Celts, and whether or not Mali replaces one or both of Morocco (function) or Songhai (geography), but in any case those three are in some flavor of jeopardy. Finally, I don't think the Shoshone were ever really all that popular as a Civ, and just about anything interesting about them (as a Civ mechanic) has already been done better by the Cree, so I wouldn't expect them either.
That leaves Assyria, Austria, Babylon, Byzantium, Ethiopia, the Hittites, the Iroquiois, the Maya, Portugal, Siam, the Sioux, and Venice.
-While I would love to see both Assyria and Babylon, I get the feeling they're probably both competing for a spot, since they'd probably rather focus on more marketable (re: medieval or later) civs. Babylon feels like the safer of the two between seniority and being infamous in V.
-I would be surprised if Austria returned unless we get more than ten civs. I really enjoyed their gimmick, even though it was more fun than useful, but Europe is pretty full to begin with (especially if they add anyone) and they're probably the easiest cut from it.
-Byzantium is awkward because it definitely has the name recognition and prominence, but I sort of feel like it would have returned by now if it was going to. I could go either way on this one if we only have eight civs left, but it should be safe if we get more. I guess it could technically sneak in as an alt leader but that'd be pretty weird.
-Ethiopia feels
relatively safe, although not so much that I can't see them getting screwed for a new African civ.
-I would love to see the Hittites but they're never coming back because they don't have enough sex appeal to anyone other than me
-People generally seem to like Native American civs but I'm not sure if Firaxis does after the Cree stuff. I don't see us getting a new one unless the situation has changed in the southwest (which I find unlikely), so if we get one it'll probably be one of the older two since they're usually "safer". Iroquois is probably more likely than Sioux for a few reasons, the simplest of which being that it's appeared more frequently, but TSL might impact this I guess.
-I feel like the Maya are the single biggest lock there is among returning civs. They were fun in V and pretty much everyone likes/wants them.
-Portugal is probably second place
-I would like to see Siam return, but this series tends to (very unfortunately) largely ignore SE Asia beyond a single obligatory civ. Considering that we already have the Khmer, I don't see them returning outside of personal favoritism, because even if SE Asia gets another civ I'd expect it to be a new one (probably Vietnam, maybe Burma.)
-Venice is an oddball. In a vacuum I'd expect to be cut, but my impression is that it was surprisingly popular for an underpowered and gimmicky civ, so I wouldn't necessarily guarantee it. Probably the biggest risk factor for it is that it competes with other Italian options, like the seemingly-canned Genoa or just a blob Italy in general.
I'd pretty much bet my account on the Maya and Portugal returning, and Babylon/Ethiopia/Byzantium/Iroquois aren't
too far behind, but unless we have more than eight civs to look forward to I'd be surprised to see all six of those survive and anyone outside of them is probably dead barring something unlikely.