Looks like when reaching end game we don't have many options other than horizontally scale factory size (copy-paste blue prints) to progress more. Getting idea from game mode rocket rush and supply challenge, I think add a random research mechaic might be interesing
It looks like while many factories being designed as using different regions to create respective intermediate products, some are actually designed as make and consume everything inside one region - raw ores/oil in, research packs out and directly conume up.