Getting close now (though have a new civic category to get icons for now

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We now have fully working immigration / emigration system what works as follows:
When a city grows unhappy or unhealthy, you're losing a war badly, or you're too whip-happy, there is a base chance per turn that effected population will consider emigrating. If this happens, you will receive a pop-up warning you and giving you the reasons, and you have an indeterminate amount of turns to address the problem before they go, if you manage this, they will abandon the move, if not, then they'll move from your city. It could be anywhere from 1 population to half a cities population (but this would have to be super severe, I've never even seen close in tests)
They will then choose a city to move to, that's weighted on a ton of factors from happiness, healthiness, target civ's wars, civics, culture, distance, and lots of other stuff.
If the city they choose is in your own civ then they'll simply relocate there, but chances are it'll be elsewhere in the world.
When they go, however, there is a chance that they will spread any religions that are in the city they leave (more likely for state religion) and also, they will add some culture of your civ to the city they move to. By the end of the game most successful cities will likely be multicultural, containing a minority of most civs in the game.
So there are positives and negatives for both immigration and emigration, if you are badly losing a war you may see lots of your population flee to neighbouring civs at peace as refugees. On the plus side, they will likely spread culture and religion a fair bit for you.
The new civic category, Borders, allow for different strategies for capitalising on the positives, and defence against the down sides.
Border patrols
- Default
Controlled borders
-50% Immigration to Civ
+10% Great People
+10% Commerce in all cities
-10% Culture in all cities
Useful if you want to avoid the majority of culture / religion spread from immigrants, but still want your people to emigrate to spread culture / religion to other cities. You have a culture penalty though since less people are coming in and spicing things up.
Isolationism
No multi-turn trade agreements possible with other civs
No international trade routes
+200% espionage
No foreign religion spread into lands
+3 happy citizens in biggest cities
-20% science
+10% production
No emmigration from civ
No immigration to civ
For the North Korea style of play. Gives a huge espionage bonus at the cost of science (from lack of collaboration in the scientific community) as well as no trade routes possible, and completely halts all immigration and emigration to and from your civ. Happiness due to ease of propaganda, and while it doesn't stop religion spread inside your civ, will stop all religion entering your borders.
Also, now that unhappiness and unhealthiness can cause much more rapid population loss for cities, spies poisining water and fermenting unhappiness are much more of a worry for other civs.
Freedom of travel
Any rival civs can enter lands freely without Open Borders.
+10% science
+10% commerce
+20% culture
+2 trade routes per city
x2 foreign religion spread
x2 immigration to civ
x2 emmigration from civ
0.5 unhappiness for each immigrant in city
the bonuses to science, commerce and culture from having truly open borders, as well as potential problems from immigration/emigration are balanced by 1 unhappiness for each 2 immigrants in your cities.
re: Wonders
The Sphinx has been added (taken from the awesome Thomas' War) with a new effect, which gives the civ all the Redistribution civics for controlling food / production distribution in your civ.
The Great Wall has been made the same hammers as the Pyramids and Sphinx, and now also provides all the Borders civics.
Specific values are still WIP, this still probably isn't terribly balanced, but any feedback would be much appreciated!