Why do I worry about maintaining my health if I'll end up dead from choking on food after reading some off-handed humorous remark on an online discussion board?
Actually, it was very carefully considered, scarcely 'off hand' - At over 3/4 of a century and still kicking, I figure I might as well acknowledge the fact that I'm Older than Dirt and have been around since the Korean War was Current Events and going to the moon was Science Fiction rather than History.
Barbarians versus Something Else.
I suggest that 'barbarian' should be based on behavior: 'Barbaric' the adjective/adverb rather than Barbarian the noun.
I've posted on this before, but nobody reads or remembers anything on this Forum posted more than a month ago, so here we go again:
Everybody should start the game the way the Civs and City Sates do now: as mobile units. Specifically, as Tribes, Clans, Bands, or whatever neutral title you want to give them.
These will be potentially, Major Civs or Minor Civs - the latter including both mobile Bands and those that settle down into Settlements on the map. The inhabitants of these Settlements may be Neutral, Friendly, or Hostile.
Friendly are like the Goodie Huts so beloved of Civ, except that in most cases, they remain on the map after you meet them - giving the potential for them to grow into City States or some other Less-Than-Major-Civilization Entity on the map, and for them to give you some kind of on-going benefit, like trade, immigration, or spreading technological, cultural, social, or religious tenets.
Hostile are our old 'friends', the Barbarians, except that you may be able to turn them Neutral or Friendly with a lot of diplomatic effort (can you spell "bribe' in Thracian, Cimmerian, or Turkic?).
Neutral are just that, but may turn Friendly or Hostile based on Events, either instigated by you or other players or even Random Events.
Note that this means the game can start with far more Groups on the map than now: the same Bands will represent potential City States, Barbarian Clans, Goodie Huts all at once, and throughout the game the map should be a lot more full of 'other people' than now - something that people have been Posting about for a long time: the Empty Map syndrome prevalent in Civ (and Humankind, for that matter) that does not represent the reality on the map for the last 12 - 15,000 years. Potentially dealing with all those Others could also act as an in-game Brake on massive expansion, because they will force you to make a decision every time you expand: exterminate, incorporate or placate? - with suitable penalties applying if you choose wrong.
To circle back to the Neolithic Discussion, nobody should be forced to immediately slap down a City with their mobile Band, because, frankly, there are a number of things you will probably need before you can make that first City work: a great many early cities Didn't and a great many early collections of cities disappeared until archeologists dug them up several Eras later. Instead, the possibility has to be in the game to achieve various Technological, Social, Cultural advances Before your first city, and grab resources from territory you pass through, so that Not founding a city as soon as possible does not also put you far behind the other players, human or otherwise.
Just about the only thing that you shouldn't be able to do without a city is make war. The best that early bands could do was harass the Heck out of city-builders, to occasionally make them move away (the Cucuteni for example) but there is simply no evidence for the infamous Barbarian Hordes overrunning anybody before they got horses and organization - After 4000 BCE.
If you think about it, that makes this 'Early Prehistory' period one in which you fight the map more than the players. That's a Good Thing, because prior to 4000 BCE the map was apt to change dramatically while you weren't paying attention. As in, century-long droughts because some &^#$% Glacial Lake half-way around the world collapsed, or the local inland sea suddenly expanding to cover your farmlands, or the great marshland you've been getting all your food from turning into a large, shallow, salt-water Sea before your eyes. Early Cities may have to be Less-Than-Permanent if you want your Band to survive and thrive: the last thing you need is Hairy the Barbarian also swinging a club at you.