Inefficient/excess farming is often a problem as each field takes up a building slot. Ensure your using the best land for farming. Minimal Irrigation (5 tiles from a ditch is irrigated) is important, so dont circle the farms with ditches because its wasting farmland and money.
3(~23 tiles/crop) or 4(12-18 tiles/crop) crops per farm is best. The greater the number of fields beyond ~30 the less will be harvested from each field; the total harvest may be more per crop because of the extra fields but the total annual harvest/farm suffers. 2 crop farms(~33 fields/crop will have lower total harvest then 3 or 4 crop farms. 5 crop farms(12-15 fields/crop) suffer a bit from the overlapping growing seasons but if the number of foods is important then it is a option.
(Wheat/bean/millet/cabbage), (Wheat/bean/millet), (Wheat/rice/cabbage), (bean/millet/cabbage) are good combinations. Avoid (bean/rice/millet) unless its the only 3 crops available.
Farm configuration can influence the annual crop harvest. Avoid the use of connecting roads on the NE or SW sides. Place the first 2 crop of the season on either side of the road so the farmers don't have to walk too far to get all the fields. About every month when each farmhand return to the farmhouse they will be replaced by 2 farmhands if agriculture isn't suffering from employment problems. When the later season crops need planting you'll have plenty of workers to tend them.
Food farms can generate 30-40 loads per year

Silk, Tea and Lacquer farms:
Overlapping configuations(5x8) work good, with 3 fields seperating each shed. Placing irrigation on one side(along the sheds or roadway) and run the roadway(3 or 4 tiles from shed) on the opposite/adjacent side.
Lacquer farms are best at 5x8 non-overlapping. They can be extended to 8x8 overlapping but you'll be using more building slots for the same harvest amount.
the sheds should generate 10-14 loads per year

Hemp farm:
Full 8x8 configuartion works good, overlapping may get a little extra harvest.
20-30 loads per year

Industry:
Don't be overproducing and storing too many things. Consolidate to what is needed for your city's use.

Short of actually seeing your city in operation I couldn't give specific details. A population of 100,000 is possible upto Hard difficulty. Even a population of 50,000 takes a bit of number crunching too be stable.

[This message has been edited by shaun (edited 01-27-2004 @ 05:09 PM).]