I finished the first phase of the space elevator, maxed out tier 3 and 4, then got distracted trying to get coal power up and running before moving on. I was getting tired of running back and forth, constantly feeding leaves and wood into a production line for solid biofuel so I'm not dependent on biomass generators anymore.
The last thing I did was set up a steel production factory using two iron nodes, a nearby pure coal node, a copper node, and a limestone node. I'm producing tons of steel pipes and beams, then feeding about 2/3rds of them into another production line to make stators and encased industrial beams, respectively. Once I've built up a respectable supply, I'll dedicate my time toward finishing phase 2 of the space elevator so I can unlock tier 5 and 6.
My wife is playing for the first time, and despite spending way more time than me building her factories, she's barely done with tier 3. I have over 600 hours in Satisfactory, so while I'm taking my time and enjoying the journey, my experience with the game means I'm progressing much faster than her. But she's really into the math of it, trying to squeeze every ounce of power and resource production out of her factories, so she's going to have a much better build than me by the end.