The All-Factories approach has been somewhat nerfed in ToA, or so it has been posted here. I play DA and it is among my favorite strategies. There are lots of older threads about both All-Factories and All-Labs.
The way I implement it is simply not to build Research buildings, but to use Focus-Research instead, channeling a percentage of production to Research. That lets Factories essentially do Research. There are lots of details, such as do racial Research bonuses increase Focus Research? Do Social racial bonuses increase Focus Research? Does the Research Capital increase Focus Research? Do Research starbases?
I never let All-Factories stop me from building economic-boosting buildings, especially on higher pop planets. Not only do i not build Research buildings, I do not waste the Research on them.
On higher difficulty games, I often delay starting All-Factory for the first ten turns or so. I ensure my Homeworld comes with at least a 300% Research bonus tile. - A 700% would be best, but they seem really rare for me in the gigantic all-abundant maps that I prefer. - Then, I buy a Research building onto that tile and put all or almost all of my resources into Researching the initial foundation techs, like Planetary Improvements that give Empire-wide bonuses, and some others. Once that is done, I shift to All-Factories, including paving over that first one or two labs.
Oh, in any fast early Research strategy, it is vital to use your first colony ship fast and to convert your miner to a colony ship and use it fast, also. The game limits the number of tech levels one can gain to N+1, where N is the number of settled planets in one's Empire. Thus, if you use that first colony ship as a scout and the miner as a miner, you cannot gain more than 2 tech levels per turn.
