I just cleaned the floors with 4 "Bright" level comps and I was wondering. I got pretty neat start getting 3 goodish planets and one lvl 6 (had to use that last colony ship on something). So there's questions some in there but it's also a sort of "Game report". The question is really in the last sentence...
I set up neat economy and everything is running well.
My ships are mostly crap, total crap to be exact, 2-0-0, 0-0-0 small defenders but enough to keep the enemies off my back. I pressure heavily on technology, getting up my economy, research and stuff, while keeping my opponents away by doing heavy trading and occasionally paying some tribute, selling some tech to minor races (well all of it) and pumping up those ships that keep getting better but don't have engines and are practically useless in any "real-time" combat.
So I gain influence and my tech rates are going to heavens. I have a stable income, everything running at 100% UNTIL I start taking over planets. Now I like to hit my opponents where it hurts, so I look up the strongest military might - the Korx. I figure that decapitating them will be the best way to handle the raising beast (who also is the only one feeling hostile at the moment). Korx was keeping other races on their knees. So I amass a few ships, armed with ray weapons, yet no armor, and a few transports. Within few turns of finishing planet invasion tech, I have researched space marines etc and am ready to invade.
Now I move my sloooooow fleet, next to the main planet of the Korx, which happened to be in a very neat place located near me. Now I manage to conquer it, even after losing quite many ships. But then all hell breaks loose! I am now making more production and research and my economy starts to collapse. I still manage to keep it up.
Basically this happens to me very often, the more planets I conquer, the more my eco seems to drop. It might be partly because of the constantly increasing shipcount as well. I had lots of reserves at this point though since there was a tax rate boom that made my income go wild for a while. Basically, I managed to totally cripple the Korx, then bought a piece for 2000 BC. Doing lots of business with the Terran alliance, allowed the Muhwelon race to finally ally them, as well as the Altarians. Ironically enough, there was a war going on between the Altarians and Terran, so while I supplied some stuff to Altarians to keep them happy and stuff. Terrans didn't mind obviously and Altarians finally surrendered their last remaining world to me. Same was soon to follow by the insectoid race that didn't have that nice of a start.
But while doing all this, a quiet race raised from the corner and actually had my fleets outnumbered, my economy was collapsing fast now. So after finishing my new Flag ship, the Phoenix Fire, armed with a bunch of nano rippers and enough shields and armor to fend of black hole gun, I flew with it and took off planetary defences everywhere and sniped off smaller fleets. They also had a problem with the Terran Alliance and soon it was over for them. I gave Korx bunch of good and they agreed to form an alliance - Yay, diplomatic victory.
In short: How do you manage lategame economy when you start getting planets that aren't balanced for your needs?