New Progression Idea
What if u get research points over time (or maybe by simply doing tasks such at mining, or assembling parts and refining ores, but not building cause that can be exploited.) and u can use them to research stuff, these would be extremely easy to get, allowing for the coolness of progression while getting rid of some of the annoying parts. You would still have to research the stuff before it, so its still a tech tree. Also you would still research things in groups, maybe divided up a bit more, but catwalk parts, etc. would all be in one group.
Edit: maybe you could buy schematics from npc's which unlock the part no matter if you've unlocked the stuff before it.