This is the first of my thought experiments about colonizing the Solar System. I’m of the view that we won’t wait until we have space elevators or anti-gravity drives. When selecting start colonizing, getting into orbit will be a lottery of effort. Personally, I believe that when humanity gets serious about the Solar System, well still be struggling to get into orbit. I suspect that an early goal for long term settlement will be a consistent and ready supply of water in orbit.
If there’s water on the moon or on an asteroid close to Earth. That will be the primary objective. To establish a settlement and a mechanism for reliably and routinely getting the water for there into Earth orbit. It could be stored above geostationary orbit (where there is less junk) and decelerated into a lower orbit as needed.
The first permanently inhabited colony in space may be on a chunk of ice. Once the cost of moving heavy propellant into orbit is removed then travel time around the Solar System can be reduced and the amount of useful equipment brought into space increased.
In my timeline, this is what has happened. The first colonies were set up to guarantee a ready supply of fuel.