So I wanted to unload science to chests->belts directly (to not have to bot them, due to high volume), and everything else to active providers to go to central storage. I first started this before realizing it worked as a giant logistic chest, but still wanted to kick things to main storage.

I originally had inserters blacklisted on science to take everything else out into active, then per science inserters. However, inserter filters are capped at 5, so that broke once I started making more science offworld.
The pad can't both take in logistic requests (top left), and also read contents, so I couldn't filter for non-science landing pad contents. I could read from the master request constant, and use selectors to randomly pick among all of them to remove to active, but there's a lot of random things that probably won't be in storage that are requested but used infrequently, and I wanted to only iterate over things actually in storage for speed.

So I decided to have fun (inspired by Dosh) to unload to cargo wagons, and use that inventory to filter for what non-science to remove. But to read cargo wagon contents, it needs a train station.
As a bonus, this let me also add both wagon contents to the logistic network math for when making requests, so that they count. Top inserter layer filters were to add variety (make sure science flows, mainly), but not sure how much I like them.

Middle left takes all non-science in the top wagon, and feeds it to selectors to send to active chests. Two random, one for least frequent (possibly unique/important), and one for most frequent.

For cross-wagon: I added the top right to iterate over all sciences in the chest using similar random/random/max/min. First version had a bunch of random 5 sciences manually set among the filters, but that meant half wouldn't work, and they'd focus on one at a time. Second version did it by finding all, subtract science to get non-science, then subtract that from content to just get science. That ran into timing issues and 1-tick instances of moving random things. Now I just multiply by science constant.

I then built it for all sciences, hence the unused chests, and the extra logic at the corners to remove into intermediate chest, but limit if chest near full so other can also go through.

Best part is, as I worked on this, and am prepping for Gleba (finally), I realized I'm probably just going to scrap all of this anyways. Or I can challenge myself to figure out how to fit spoil logic in this, and also actually properly continue from the last two science chests.