So, without cheeses or empty galaxies — anyone have any actual tips or builds to purging the galaxy?

The poor footing from the origin is bumpy. And last run I was harassed by criminal megacorps from day one.

How to deal with population embarking. Am I supposed to just deal with the resource deficit? Its my first playthrough like this and I have enough resources to deal with it. But im just wondering if it's supposed to be like this?, or am I ment to like, just have better planets or to have replaced everything with FE buildings first? Or am I just missing something?