Agreed. I think there needs to be a much slower progression overall like a "Long war" mod that draws out everything. Having more variance in what each industry produces or enables production of (this would be a significant change overall). Maybe light industry allowing the production of frigates and destroyers or something along those lines.
Currently there is only early game = making money in preparation for colony
and
Post-Colony = printing money. If you have the starting capital (1 mil) you can essentially take a sub 200% planet with decent ores and turn it into a 150k to 350k profiting colony in under 8 months while still upgrading the port, GD, Orbital stations etc. That's a very rapid change in player income that snowballs in our favor too quickly imo. I think a more practical expectation on a perfect planet would be more along the lines of 50% increase in revenue annually, not several thousand percent in a matter of months. Maybe a more dynamic way of managing a colony is needed like assignment of population (colony size 3 gets 3 assigned personal to put in industry or construction of new structures) with each assigned personal modifying construction time, production, growth, etc. Need a structure quickly, assign all three and stagnate your population growth and mining production but increase the construction time by 30% (not additive) for each colony personal assigned (3 personal = 50.9% increase for instance)