Hello, i love your mod and i wanted to point out some things.

This is for v0.2.10a

Feedback:
First of all, there is a cross between two techs of your tech tree. Harpooning and Tool specialization. Harpooning is at the bottom and Tool spec. at the top. The "daughter-techs" of these two technlogies, however, are inverted. The "daughters" of harpooning (wich is at the bottom) are at the top and the daughters of tool spec (wich is at the top) are at the bottom. Making it very difficult to understand because the linking lines are all mixed up. You can simply switch positions between harpooning and tool spec.

Also, the fact that you can create caravans before researching caravanery is quite unrealistic, perhaps you should move caravanery just after trading and make caravans available via caravanery tech.

I recommend giving just one movement point to units in prehistoric age because by the ancient age you alredy know the entire continent, that kills the immersion of being an isolated tribe in the dawn of humankind. Having 2mp is like "yeah, lets go on vacations to that peninsula, you know, the one behind the desert to the right of that mountain range" while having just 1mp is like "the explorers tell us that beyond the Hill of Silence runs a Great River, nobody knows where it ends or where it begins, but the legend says that it goes beyond the end of the world".

Suggestions:
The tech tree is too long and you have nothing to build because of that, there are many techs that only give you one thing. More buildings or less technologies are required. I made a proposed new tech tree that keeps all the units in their respective place regarding number of techs needed to obtain them, but decreesess some unnecesary techs and renames others; it tries to keep your units/building/features unlocking rate intact (so if warrior required 4 techs, it still requires 4 techs). Might be you wont use it but it may give you some ideas that you can pick from it.

http://i.imgur.com/Gi4bEiK.png

An idea for nomadism.
Instead of trying to build destructable cities (which is very difficult because your capital is indestructible) and constructing buildings inside it. Why not having a unit called "Tribe", this tribe can be in "move mode" or in "camp mode", it changes modes exactly like the trebuchet. In move mode it is like a settler (but different so you can differentiate them), in camp mode it is like an encampment (You will have to create the model, perhaps importing the goody tribes model from civ IV).
When it is in camp mode it generates research and culture, so they can go fast through the thechs of the prehistoric age to the ancient age, however, it does not "grow".
If the tribe is in move mode, every time they move from one tile to another they will gain a little bit of experience ("FOOD for GROWTH") it represents the fact that the tribe is chasing the animals and wasting the plants of the area and thus having a surplus of food to feed their children but do not have time to stop and think about life like when they are in camp mode. When you fight you get experience too (the stolen food after the skirmish).
So its convenient to keep moving "chasing" the food and earning big boost of experience (food) from fighting the barbarians but also stay as a camp to generate research and culture, so you would have to balance and manage your precious turns "camping" or "chasing food". When you earn enough experience (food) you can choose from one promotion, each promotion represents "a new member of the tribe" so if you choose the promotion "Scout", the "new member of the tribe" (the new promotion for the unit) will be a scout and thus will give you +1 sight. This would be the substitute for buildings and citizens.
Other examples:
-Promotion Shaman: Heal reate +10%
-Promotion Scavange for medicinal herbs: Heals the unit
-Promotion Elder: +1 research when in camp mode.
-Promotion Scavenger: +1 movement points
-Promotion Scout: +1 line of sight
-Promotion Toolmaker: +20% strength fighting barbarians
-Promotion Hunter: +20% experience when moving into grassland or steppe
-Promotion Gatherer: +20% experience when moving into forest or jungle
This can also be buildings of the tribe:
-Promotion food storage: 20% experience when moving
-Promotion Palisade: +20% defense
-Promotion Longhouse: +1 culture
One promotion would be called "Create new tribe", instead of gaining a promotion for the tribe unit, a new tribe unit will appear next to the old tribe unit. This means that the "new member" decided to create his own tribe. A warrior (authocthon, savage, etc) can be created using this method too.

Technologies instead of giving buildings or units, they make promotions available for the tribes, for example, the technology hunting, unlocks the "Hunter" promotion, the technology warfare unlocks the "Create new warrior unit" promotion (and therefore unlocks the warrior unit) the thecnology complex tools unlocks the "toolmaker promotion". The technology agriculture would grant the hability of settling new cities for your tribes. You may not "train" new tribes from the cities, therefore ending nomadism with agriculture.

Help proposal:
I took a prehistory course recently and i have all the classes in video. Its a very interesting course that i think you will find extremely useful. If you want i can email them to you. There are about 4 hours of video, dont worry about the copyright, everything is ok if i email you ONE copy of the vids, just dont show them in public, dont make monyey of them, etc (you know the usual copyright sensitive stuff). The classes were given by a PhD in history of architecture.