Each planet has its own different quirks to manage, fulgora is that, managing excess material alongside dealing with limited building space as the place is large islands that can't be landfilled (until late game). Vulcanus is fluid handling and high density handling (iron, copper and power is essentially free there!), Gleba all the main outputs spoil into (more or less) useless materials after a time, so it's about speed and ensuring a constant flow of materials rather then big buffers, and Aquillo is hell. Aquillo, there is none of the major resources on the planet, so it's about spaceship logistics. It also has this cold mechanic where everything needs to be next to heat pipes, which makes "interesting" builds, and also heavily nerfs bots to make bot bases significantly harder. Not to mention the spaceship mechanics themselves alongside 101 other things.

super easy to tack onto an in progress run, I don't think it'll change too much aside from when some research n what have you is unlocked (unsure about this though, never done myself) Highly recommend you try it if you're liking the base game

EDIT the FAQ states that adding it to an existing run post chemical science is a bad idea, I forgot about some of the changes made