The question is - at which point of the y0 did you end your game?
If you're ending very early, on April/May or so - I wouldn't even dare to raise pop. Go full tax ever.
But if you're outplaying until 22nd 12, you can raise your pop, okay, but in the very beginngin your HW has already much pop. Those 8b ppl are already enough to get some good tax-income.
The way how taxes are collected is to the square-root of your pop. So if you have 8b ppl that gives a factor of ~2,8. Now let's assume you want to raise pop (normally, not with Breeder) until 12b ppl, then you would have to do 10 turns with low taxes (10*0,4b ppl = 4b +8b =12b). However, your factor for tax has only increased a bit, to ~3,4. That's just 0,6 more taxes in the end. So trying to up your population on your HW is pointless.
However, things are different when you colonize a few other planets. To cut it short; the factor of a 0,5b HW is ~0,7; but that of 2,5b world is ~1,6. More than twice, although you even have less than 2b ppl more on that world. In the above example you had 4b ppl more - which was worth nothing.
So the best you could do is to ferry the population from your homeworld to other planets that are nearby, or take Big ColonyShips and colonize a few other planets. However, you'll need money for that, and this is something that is sparse within the first 8 turns - in which it is better to focus on Tech research solely.
But actually, that's up for you to find out. Why not? Develop your own strategies. The game will tell you (via score) if you did things wrong or better.
Yeah - the gigantic. How are you going to solve the range-issue?
Edit:
BTW just noticed you are already ranked #1 in Kryo's AltMeta in the Military Solar-category. Ascanius.
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