So am I understanding correctly....
- Ideally, you need to keep your total number of potential output (the gross number before any bonuses or penalties, e.g. the raw base output potential of the sum of your "labs") to be exactly equal to your empire potential (the red number in the top right)? And assuming you want to research with equal speed in all three areas, your total gross potential in each area should be exactly 1/3 of that red number?
If you have any less, you are not utilizing your potential. If you have any more, you have empty labs.
In other words, if my empire has a potential of 1200, and I want to research equally, I should have 400 in energy, 400 in HT, and 400 in weapons labs before bonuses or penalties. Any more, and I am merely paying upkeep. If I then build a weapons research station with 4 labs at 50 each at a location giving me a bonus of +50%, I would have 400 / 400 / 600, and increase my net weapons research by a bit, but I would also reduce my HT and energy research. Right?
(So this also means that once your research potential has been decked by your labs, you can stop building those default designed spaceports with labs in them, because those won't be doing anything anymore, right?)