I think the OP wanted to see how you can raise money in the normal way, not by selling stuff..
But, IMHO, I always though that having morale bonuses is much better than any economic bonus. Morale allows you to have more people on planets, which means much more taxes.
Example: Think of it, you already have a +10% economic bonus (ressource? race?). If you take another +25%, you increase your revenue by only (0,25/1,1)%, since I don't think the additionnal 25% is composed with your former 10%. However, if you take a 25% morale bonus (speculation about the numbers), you may have 20% more peoples, and they ALL benefits from whatever economic bonuses you have.
The point is, to have a strong economy, you must not put all your points into economic bonuses. A good balance of morale, pop. growth and economic is usually much more profitable..
telling you, in my actual Yor game, I poop 1500 BC each week, which is much, much more than any other player. My research is kinda low, however..
You should have seen when I made 6000 bc/week because of the Economic prosperity random event