Is it really a pity the AI won't build Cargo 2/3, if it isn't smart enough to do anything but lose resources by doing so?
This, though, is the sort of thing that makes me really want MM to make it possible to add an unlimited number of ability tags with whatever names the modder wants. It would be really nice to be able to put in the design file "Cost-efficient cargo" instead of "Star - Unstable", and to not worry about side-effects or running out of usable tags.
As for system tags, yes, I think there may be a couple of funky ones allowed for home systems - I should review that. Meanwhile, enjoy the novelty. Too bad you probably didn't take Crystalline tech.
PvK