How do I build large, healthy cities in Simcity 4?
There are two ways I commonly break my cities:
Spending Money On Things Before Sims Want Them
Sims want things... schools, hospitals, parks... but they want some things more than others, and if you build them in the wrong order you are WASTING YOUR MONEY, because they don't have their full effect. On the quick reference guide, as well as buried deep in the Sim City Manual under the desirability chart, is possibly the most important information to the game that no one knows:
What (Sim City) Sims Want
Although you can’t directly affect the types of occupants that develop in your city, you do have indirect control by affecting the desirability of the zoned areas of your city. The following actions can be taken to improve the desirability for each of these occupant types:
This chart is ORDERED. Residential Sims want police more than hospitals. Dirty/Manufacturing industry wants police, then shorter fright trips, then NOTHING else, they're happy. After you've taken care of the basics that every zone wants, power and water for higher density/$$$, take care of problems in this order and you'll spend less money, attract more Sims, and make more money. I'll repeat once more:
I think this is the most important info people are missing to building a great city.
Not Replacing Dying Utilites
The utilities buildings, water pumps, power plants, and incinerators age over time, more for the more they are used. They gradually cost more to maintain and have lower output. Eventually, you are paying out the nose for nothing. Replace them as soon as you can.
Special note, if you are using Waste To Energy incinerators, turn them down to producing no power and have them only dispose of waste. This prevents the plant from aging in any noticeable amount, and you can then buy your power from a cheaper plant. The downside is that your power budget will not be at 100%, so 1) new plants will start at whatever the budget is set to overall, and 2) there is a chance of fire on all power lines. So just don't use any... use low density commercial zone instead. Same power spread, no cost, possible income.
Unfortunately, the game is pretty brutal out of the box. The distance a sim is willing to travel for work is rather pathetic, which means you have to build your commercial and industrial zones very near your residential areas.
Try using the Network AddOn Mod (NAM) to round out the types of roads you can build and increase the distance sims are willing to commute to work.
Also, Simtropolis is the single largest online community for SimCity and they have thousands of helpful users on their forums with invaluable information to help you succeed at city building (not to mention the Simtropolis Exchange (STEX), which has tens of thousands of user created buildings, models and mods you can download to enhance the game).
I've not played in ages, but I seem to remember that the trick was to not become too attached to any particular segment. That is, if you spent a lot of effort building-up a big commercial area, let's say, then it starts to falter, be willing to bulldoze it down and make something different, if that's "what the game wants."
I also seem to recall that making lots & lots of "mini-cities" -- neighborhoods that were nearly self contained, with a nice balance of parks & rec, industry, commercial ("strip malls" :) and residential seemed to work well. It helped cut down on commute-time, which I think my little sims liked :)
But, again, you have to be pretty heavy-handed with the bulldozer (not all at once!), and willing to make constant adjustments as this or that area gets too much THIS and not enough THAT. In general, I'd say that 10% of any given city was ALWAYS "under construction", and that 10% moved around a LOT.
Also: I think it helps to always repair damage (disaster or rot) as quickly as possible, and spend the money on police & fire services.
Hmmm, now you got me itchin' for some 'City -- gonna have to dig that out! :)