In FAF i seen a lot of mods that made eco easy, reclaime drones, experemental mexes, x2/x4/x10 storage rush and more. But there no mod that tweaks mass fabricators. Like returning mass fab balnce that was in vanila game before FA, and add one more level of massfabs. So it will be t1, t2 and t3.
Lets say for example that t1 will be like vanila t1 - 1 mass for 40 power, and that will be to efficient, but still usefull for same purpose that exmex mods
If t1 will be like now is t2 - 1 mass for 150 that prevent from mass it in t1 stage. T1 and mass fabs can be somethig between FA and vanila 12 mass for 1500 power and 24 mass for 3500 power. That more power efficient, but can be balanset by cost a time to return that cost and bring a profit.
Even with that it too good for turtle play, but can be usefull for some maps like Flats for example. Another tech level of fabs request model for it, but, for that can be uset models of some civian buildings, i think.
That will not be integrated mod for sure, but there is exmexes and ninja drones, so, why not?