What I've learned so far due to my perverse obession with turning the worst possible hellholes into actually 'nice' places in every game with any kind of population management.
With the escalating upkeep costs as the colony grows, a planet with a rating of >125% will be unable to support any form of industry or fuel production unassisted in the long term.
While it might make a profit at size 3 and 4, once it grows to size 5 the upkeep costs start to outpace the profit generated by exports.
Adding nanoforges and synchrotrons will not boost production enough to offset upkeep on 150% and higher. Prioritise them to improving your already profitable industries. And use whatever is left over wherever they will fit.
Adding beta cores will allow you to run a full set of industries upto 250% hazard. (50% of 250 = 125, which is the max hazard value for industrial profit.)
IF you also have the Industrial Planning skill (or hire someone who has).
Without this 30% boost, you can only go upto 200% hazard.
The extra production from alpha cores does not generate enough profit to extend this meaningfully. Although you may wish to use them to offset shortages.
Enabling free port will allow a colony to use all industries on a 175% hazard world without AI cores and still make a profit. Although, once it grows to size 7 you will not be able to turn it off without installing AI cores to reduce the upkeep.
If you do enable free port, make sure you also have a light industry running.
(Light industry is a bit of a conditional trap - It's incredibly good when combined with free port due to all the drug money. But if you don't want to use free port, it's the sort of thing you build one of somewhere with low upkeep and have the rest of your empire just forget it exists.)
Using cores and free port on a low hazard world is basically cheating.
Compare and contrast the harshest readily available world I could find.
Colonised solely for delicious minerals and some minor contribution to system defence:
The same world turned into a huge industrial complex with every bonus I could throw at it:
Spoiler
Approx 16x as profitable. And this isn't even taking into account the extra accessiblity the free port will eventually give.
tl;dr - If you don't want to do things to give the factions even more reason to hassle you, you are going to want to limit yourself to planets with a rating of 125% or less. With the sole exception of bare-bones mining outposts to cover needs.