Right now generators discharge extremely slowly (500kw each at base quality). Any chance this could be changed to be demand-dependent? They are batteries, after all.

Do you have a specific upper limit in mind? In Factorio it's the generator that is limited, not the battery.

I would adjust the base rate to around 1-1.5mw discharge rate if it had to be fixed, to make it a bit more viable. My general hope is to be able to run a Fulgora base without needing hundreds of generators.

I went a different route and added new batteries, chargers and generators which are available via Fulgora.