Hi. 6 planets should take you a couple minutes, not a couple hours. You're screwing up really bad, but we should be able to straighten you out
If you just want success against easy random 3v3:
1) Pick colonizer as your capship (any race).
2) Send out scouts, then send colonizer capship to the first asteroid you encounter (there should be one connected to your homeworld in most circumstances). Colonize.
3) IMPORTANT: After colonizing ANY planet, immediately upgrade the planet (first button on top left). For asteroids, do it once. For any other planet, do it twice. Then build all your extractors.
4) Build basic light frigate until you have no more fleet available. Fleet up to the next level (if necessary), and build a few more. Get 15-20 disciples/cobalts, or 10-15 skirmishers if playing vasari.
5) Colonize any and all remaining planets.
6) In the early phases of the game, there is no need to fleet up any more than what is discussed, and you never need to fleet up unless you plan to build ships immediately after.
To answer your questions:
- Population is # of people on your planet. It controls your tax income from that planet. The more people, the more tax income. Naturally, asteroids will have the least potential for population, and nice juicy terran planets will have the most.
- There is a post by Darvin3 somewhere on this forum, telling you some of the best techniques for colonizing. I will let someone else link it for you.
- You don't determine tax rate on planets, but you can research a higher level of population growth of certain planets (thus higher tax income) under the civil technology tree. Also, the more times you upgrade a planet using the first button on the upper left, the higher the population can grow, thus higher tax income.
- Keep fleet as low as possible until it is time to go to war, then fleet up to what you need to crush your enemy.
For more money, you will need trade ports and refineries, but that's another topic for another day.