Is it intended to import oil-based products?
I am not able to find a way to produce petroleum gas (and therefore sulfur and sulfuric acid), plastic, or anything else related to organic chemistry.
Usually, every "early" planet is capable to support itself and importing products is more or less a matter of connivance.

Is this different on Hyarion?
Do I overlook something?

Hi, Hyarion in its early game don't need any oil based products, the rocket recipe is different, but the post first science does so hyarion needs other planets for certain imports (Arig is very good producing those)

Ahh, this is helpful, thank you!

So the new rocket silo recipe isn't just the "local version" with changed ingredients, but also feature different ingredients for the actual rockets!
Who would have guessed.
Seriously - who?

So my suggestions you ask for is: Maybe hint this in your (in-game) description! When players sees a new rocket silo, they don't necessarily assume, that the rockets themselves will need different ingredients as well. Sure, this is usually true for all other machines, thinking about it. But their new processes are referenced in-game so the player knows, what they are required to do. The new Hyarion rockets are not.

So I guess I will recycle my handcrafted standard silo and build me a Hyarion variant then.

UPDATE: No, apparently this isn't necessary!
Trying it out in my game, the non-Hyarion rocket silo hand-crafted with traditional ingredients also features the new rocket parts. I simply would have needed a little bit of imagination and try it out. roles eyes
On the other hand, this doesn't honor the in-game logic either. (Which is stated above: new machines for new recipes.)
So again: please describe this on your mod page or in-game.
Or better both.

Thank you again!
I am happy my Hyarion run isn't over after all. :)

Sorry! my mistake for being clear with the rocket recipes, i will add a comment to the technology description and the tips and tricks page in the next update.

Don't apologise! My comment wasn't intended as an accusation, and without people like you, there would be no mods at all.

I'm glad you decided to follow my recommendation and improve your already beautiful mod. I love it when mods add distinct planetary visuals in addition to interesting game mechanics! Yes, I am this superficial. ;)