Suggestion: Self-Assist Setting for Factories

When I need Fabbers fast, I set my Factory's Units (Fabbrrs) to Rally a short distance from the Factory, and then (holding shift) Assist the Factory, allowing me to make a tonne of Fabbers quickly.
This works for one Factory at a time, but en-mass it's time consuming to tell individual Factories to Rally, and then Assist.

A self-assist button in the Build Bar would be handy here, so we could build 5 Fabricators at the start of a Queue, and then be assured that even with 100 Factories and 500 Fabricators, each Factory would have 5 Assisting Fabricators moving things along faster.

Ideally, it will be more cost-effective to just build things from factories than to use assisting fabbers en-masse (along with building the extra power needed to support them). Right now, that's semi-true for regular assisting fabbers (see https://forums.uberent.com/threads/a-look-at-the-cost-efficiency-of-fabbers-and-factories.59514/) but not for combat fabbers.

If such a thing were true for all fabbers, then that would cut out the need for mass-automated factory assist - you could just build factories and set them to producing stuff.

Also, for large projects like nuke-building, you can set the fabber-producing factories to area-patrol over the build zone - all the fabbers they produce will automatically assist anything in the patrol area.

While I agree building more Factories should always be preferable in the long term, I should still be able to tank my economy easily for the early-mid game expansion or when I'm in a tough spot.

Select the factory and right click on it. Units will now automatically assist as they roll off.

That's what I do... It's just rather labour intensive on a large scale to do so individually.

If all your factories are near each other, you could also set a patrol path right along them as the built-unit-behavior. Units that can build will assist factories in range of their nano-lathes when patrolling around them. That way, you can select a group of factories and give a single order.