I totally apologize.  I just noticed that you posted this under Gal Civ III.  My response is for Gal Civ IV.  Haven't played Gal Civ III for a long time.

Yes, I absolutely do.  I can usually get at least 1 planet up over 300.  Here are some of the things I do (in no particular order) to boost planet income.

1. Find a planet with high base income and at least 28 tiles to be you Income generating core world. (in this case I took over a planet thru cultural domination that was better than anything I had).
2. Use a Governor with the Income bonus if you can find one, but a Governor 
3. Colonies a bunch of feeder planets to send income to core income planet.  Make sure you pick Orbital Market as one of the Orbital upgrades on each colony.   
4. Build as many Financial districts as you want (Toria has 13, but I could do more). 
5. Build a couple of Housing districts to boost pop and and make a bunch of citizens with high Social Skill Entrepreneurs (I have 7 out of 13)
6. Research "Genetic Architecture" to boost all citizens Social Skills by 3
7. Unlock Ideology "Self-Reliance" under Individualism.  This will also boost Social Skill by 3.
8. Surround your planet with Economic Star bases -adds 5% each (I usually do up to 4, but only have 2 around Toria currently).
9. Add Trade Station modules to each Economic Starbase.  
10. Build a "Governors Manor" on a tile that boosts the Gross income bonus to at least a level 4 (that gets another 20%)
11. Build Mining Bases on any nearby asteroids for another income boost.   
12. Check out the screen shots below for any other hints I may have missed.

mokus5679 - see post below for Gal Civ III info.

 Thank you very much for your response plus screenshots. I found out that Terain are not a good race for economy since their best economic improvement is shopping center which is only tire II. I found out that Iridium are excel in economy so I consider them later if I want to get the advantage of economy.

 Thank you very much for your reply. I also recognize that my economic planet somehow makes much less tourism income so apparently it makes much more money than I first thought around 150 credits.