Qin Shi Huang's Chinese
Financial + Industrial sounds very practical. For industrial, there is 50% bonus wonder production, and 50% faster forge building. For financial, there is this 1-extra-gold bonus on 2-gold tiles, and 50% faster bank building.
I like to chop 3 workers at the beginning, and make them chop more for stonehenge, oracle, and pyramid as early as possible (stone resource) in the GP farm.
Except for your future production city & GP farm, cottages along the river (2 food, 3 golds) helps a lot. Only build cottages on 1-food ties after all 2-food tiles have been harvested.
Early-on over expansion with Qin Shi Huang may not sound right at higher difficulties, because our emperor is not Organized. Your research rate might drop and will lag behind for a while, but thanks for your financial trait, you will start to pull off around medieval age. In one of my games my research rate had to drop to 0%, but I still pulled ahead at Guild/Bank. If that sounds too risky, then stick with the 50% research rate rule would be fine.
I find that one worker / city is a nice ratio to work on. You don't pay too much upkeep, and they finish the job at the same rate of your town growth. No improvement built too early or too late.
All towns (except the GP farm and production center) -- build nothing but cottage and windmills. Watermills are tempting, but cottages are much better in the long run.
Great person farm: Besides lots of extra food, this city better has a lot of forest nearby, because you are going to chop rush a few wonders here for the GPP boost early on. The most important ones are: the stonehenge (since you are not Creative), the oracle (for the free tech to usually alphabat), the Pyramid (if you have stone), and the Great Library (for 2 free scientists). All flat tiles are farms, and all hill tiles windmill. Oh, and of course the national epic.
The most useful type of GP is the engineer for wonder rush (Parthenon, Notre Dame, Taj Mahal, etc.), then it might be the artist for a fast land grab. Later on when your cottages prosper, the great scientist + academy becomes significant.
Production ceter:
The emperor is industrial, so Forge is a top priority everywhere. We still need a production center, since we want everywhere else to spawn cottages. Pick a place with at least 4-5 hills, and some extra food. No windmills on the hills - only mines. No cottages on the flat land - only watermills wherever possible, and then the rest workshop. Later on with State Property, those workshops will kick in nicely.
Tech Research
1) Bronze working (chop trees) -> Wheel -> Pottery (for cottage) -> Writing.
2) Food techs. You can really skip most of them. The AIs will trade them to you even on Deity. Fishing really helps a seafood city to grow, and allows you to harvest from nice inland lakes (2 food, 3 golds).
3) Depending on how well you are doing, you can risk for chop rush Oracle (Mystism -> Meditation -> Priesthood) then pick the almighty free tech Alphabet. Or go straight for Alphabat. You can tell whether you can get Oracle by how much time you wasted on food techs. If you didn't bother ANy food tech, and you picked some essential techs from goodie huts (such as a free Bronze Working, everybody's daydream), then you have a good shot at Oracle. It is actually CHEAPTER to research Mystism -> Meditation -> Priesthood combined than Alphabat alone. If you have lost of forest and at least 3 workers, chance is you will have the Stonehenge, the Oracle, and even the Pyramid. Otherwise, don't bother with the earlier two. Focus on the Pyramid. You really need the happy faces on higher difficulties.
4) Trade for Mathematics, and go for Drama -> Music (free great artist, and theater is the cheapest building to give culture, and the AI seldom travels this route meaning you can trade it for other useful techs). Then follow Metal Casting for a forge in every single city of yours.
5) Currency (market for smile faces, and you can finally sell cheap techs to weak Civs, lots of cash from this point on) -> Code of Laws (court houses saves a bunch on higher difficulties) -> Civil Service (Buracracy in capital). Then you will have machinery & construction, ready for another wave of expansion with maceman, preferably before your nieghbors even get their longbow man.
6) Guild -> Banking. Your win is usually in the bag at this point. Your income is flying, and the AIs start to drag behind in tech more and more. You can prusue all kinds of victories from now on -- I like to finish off my neighbors for all those agreesive town spawnings surrounding my well-planned cities.
Special Unit (Cho-Ko Nu, the powerful crossbow man)
I find them pracitcally useless, too bad.
You need to have Machinery to build them. But if you have Machinery, you are one step short of maceman (Civil Service). Both Cho Ko Nu (STR 6) and Maceman (STR 8) have 50% bonus to melee units. Even if they are in the same stack while defending, your maceman (STR 8) usually takes the field because they have a even better winning odds.
If you ever needs Cho Ko Nu, then you are defending a city. This means you will watch helplessly that the enemies pillage your improvement to nothingness. Also, you are not doing very well in diplomacy. If possible, in advance, bribe someone to deal with the aggressive Civ, or bribe themselves to attack someone else.