Removing the "rocket-silo" entry from the AAI Affordable Industry mod altogether seems to fix the game progression dead-end issue.
Ironically enough, the Space Exploration mod seems to already use the Advanced Circuits instead of Processing Units AND half as many electric motors. So I'm not sure why AAI AI had that change included in the first place. I'm assuming it might make more sense in the context of not having SE involved. I'm too lazy to look into it further though, all I care about is the fact that I can finally progress through Rocket Science Packs and beyond.
Having the change in a publicly available fork would be beneficial for others (including potential friends I've yet to drag into Factorio to play with me) though, so lmk if my solution actually helps and un-breaks the fork. I might look into doing the fork thing myself later, but aforementioned laziness is winning for now.
