Economics, Economics, Economics

I had a lot of trouble getting my economy to work out until I starting trading tech like a madman. You can work out very lucrative deals with other races for long periods of time (I like to go for 12 months myself). If you are careful (don't give military tech to your enemies), you can make enough money to out produce them. Remember, you can trade the exact same tech to a lot of different races, so although you are helping your enemies out, they are doing a lot more for you in return. Also, minor races always have a ton of money to buy from you.
V

First start with Soil and Habitat improvment. Anything that boosts PQ is a huge boon to your economy. Taxes come from morale, population, and PQ and morale comes from population and PQ so PQ gives you double bang.

Then go for Banking Center next or Fusion Power plant and then Banking Center if you have that. Anything that boosts your production is good for the economy because it lets you build the econ boosters that much faster. In the long run getting an econ boost 15 turns earlier because of the production boost is worth the maintainance on the production booster for all but the worst planets.

Stock Market is the best social project to build as an econ booster (every planet should have banking and stock market). Its a 25% Econ boost plus morale and influence. Economic Exchange is good too but takes forever relative to a stock exchange so i only build it on the better planets.

Watch your morale. For any PQ 18 or better (an PQ 20 especially) planet there is no reason not to have 100 morale at all times. A simple cheap Entertainment center is all you need in the early game, maybe add a News Net or Embassy for a small edge in the mid game and a Stadium in the late game. That and shipping your population off planet periodically should keep it at 100. This is key for 2 reasons. 1 higher morale effects taxes directly. Plus the higher your morale the higher your approval rating which means the higher you can set the tax rate without pissing people off.

REALLY REALLY try to score an econ starbase. Econ, Military, and Morale in that order are the most important resources. Before they nerfed morale, Morale was the most important resource but its pretty easy now to deal with morale without one (although with one you can get ridiculous like 90% approval with a 90% tax rate and even the crap planets at 100 morale). Upgrade that to the max mining level you have. Be willing to go to war to get one. Even better, park a constructor next to one and then bribe an AI to declare war on the owner. When the AI destroys the owners starbase, slip in and nab it.

Population boosters are great. The best thing you can build for your economy is the Aphrodisiac. Why...taxes are based on population, and nothing kick starts pop growth like Space Oysters. Take a look at the game where you're getting economically crushed by the AI...chances are their POP is hugely bigger than yours. This is because the AI is able every turn to adjust its tax rate and other variables to ensure maximum monthly pop growth...something no sane human can do. So use a hammer like Aphrodisiac and a couple of the techs to boost your Pop Growth score. Well run you can have the best economy and the smallest pop...but a bigger pop helps alot.

After this, pursue Trade. Trade is vital but pick your partners carefully. I prefer to trade with the minor powers because since they make money too I'm not helping out any of my enemies. Plus the minors will never invade me (as long as we don't share a system)and you won't lose the route from having war declared on you as often.

Also look to obtain tribute from tech sales for those times when you're running in the black.

The early game is crucial to laying a good economic foundation, so make sure you have a solid initial expansion strategy that allows you to claim a sufficient number of planets in the early land grab phase.

Theres alot of variables to juggle, but once you master them...you should never be in a position where you're out of money...at least not for very long.

humane,

You should also not worry too much if you're outpaced in the early game. The AI races tend to hit a point of equilibrium (varies based on race, intelligence, and positioning) from where they don't grow much, and where you can keep growing (if not expanding outward). Eventually, short of some fairly powerful random events, you should be able to overtake the AIs.

Of course, you should also aggressively trade for cash.

~SDC~

These are all great responses and suggestions. A bunch of you guys should get together and market an unofficial strategy guide.

Thanks again.
Humane

The need for a sequence, and the nature of it, changes dramatically when you hit Crippling - or at least, it did for me. I am still refining my sequence, but at the moment:
(a) Production Improvers - because they let you build the rest
(b) Economy Improvers - Doh
(c) Planet Improvers - more important than B to me, but I seem to have a finance crunch in this part of the game, so banks come before soil enrichment
(d) Research Enhancements
(e) Misc - NewsNetwork, Embassy, Entertainment Network
(f) The big ticket items (Econ Exchange etc - anything more that about 200)
(g) Ship Enhancements (for fleet building planets only - don't build on lower quality worlds)

When I get a new item, I slot it into this general build sequence.

Comment on morale improvers: the only one I build is the News Network, and that begrudgingly. The others are all too expensive, and I believe in a low tax environment anyway.

Like many others, I divide my planets into roughly 2 categories: good worlds, where I will build starships etc, and less good ones, where I will build constructors. I allocate different governors to the 2 sets. Currently I put econ and research onto all worlds, but this is one of the things I am looking into at the moment.

I find that I need to revise my strategy at key points at each increase in difficulty level (and I'm playing at higher levels than my current posted metaverse games would indicate - just haven't finished any. :-/ ). Some increases provoke more dramatic changes than others, of course.

~SDC~

Phaedyme, once I reached normal, my basic strategy hasn't changed much, though the 5BC/turn maintenance on starbases is really going to hurt, as I usually grab about 4 resources early on, and that 20BC/turn is really going to cramp my economy. Then again, with the morale nerfs, I can probably get away with higher tax rates to compensate, unless that gets un-nerfed.