Crafting the glass rocket silo has no advantage over the vanilla rocket silo. It uses the same amount of blue chips, LDS and rocket fuel, but requires magic glass in addition. Secondly the glass rocket silo still requires electric engines which are not craftable with Igrys resources alone and need to be imported. And to get to the glass rocket silo I need Igrys' mineral science pack, which I can't send back to Nauvis without building a normal rocket silo first and importing all missing resources for that.

I feel the glass rocket silo should give some advantage over the vanilla silo, like a productivity bonus.

+1 to this.
I noticed the same and was confused by it.
You can't research the glass silo without exporting igrys science (or importing all the other packs, including Vulcanus, as well as the labs since there's no iron.. but I already have biolabs when I got to Igrys, so I'll be exporting).
Also, since the glass rocket parts are strictly more expensive than standard ones, it makes absolutely no sense to ever use the glass silo/make glass rocket parts.

(edit): as a suggestion, maybe make glass rocket parts require rocket fuel, processing units, and glass only? (remove LDS from the recipe).
That would also make it so that you can actually automate exports without needing to import LDS from other planets.

It has. It requires 20 parts to launch instead of 50 that the normal rocket does.

But yeah, allowing it to be researched without needing to import science first is a good suggestion

ohh, I see. I must've missed that part when reading the description of the glass silo. Huh, that does make it quite valuable, and makes it worth considering to export glass to build glass rockets..
A way to make that more clear (IMO) would be to have the glass rocket part recipe produce more rocket parts, rather than reduce the number of crafts the glass silo needs. I look at recipes far more than I look at the description of items.

There's also the other issue of being unable to automate exports without imports due to there being no way to make LDS, but if that's how you want it, that's OK. Not all planets need to be self sufficient!

You can make LDS, plastic has a new locally craftable recipe, steel is the result of cermite processing and copper, well copper is abundant

With modifying the rocket parts recipe, might be a good idea

Huh, I somehow failed to notice that as well.. well, now I feel silly.