Here is a trick I've found. Surely others recognized it too but for those who didn't:
For example you got class 4 and class 10 planets near. First colonized planet should be poor one and only second colony ship should move to high quality one. When you colonize first planet a video about first col, start to play - that means that planet NEVER can get choice option - like good/neutral/bad option and that means bonuses for rich planet are lost. if you "discharge" video on poor one then rich one can get that powerful bonuses - up to +40% to PQ (so class 4 can become 6 whyle class 10 can get whole 4 or 5 additional squares or powerful bonus wich would be more useful for large planet)