Would it be possible to slow down the response time of the coal/nuclear reactors, or just change the output of all "slow" generators to full blast all the time. So the Coal steam turbines cannot just magically respond with the exact amount of power needed. Like your accumulators. So fast energy only comes from fast responders like accumulators... make all energy output's like solar to drag behind the demand.. constantly going up and down on a max slope of response. like in morning and dawn when solar cannot react and accumulators have to supplement :) .. Just a thought.. A great mod made you have :) i like it.

Slowing down boilers or steam engines is not easily possible at least, maybe with a lot of script shenanigans but it would also have bad performance considering how many of them you have in a game and so this isn't something i will be looking at.

As for nuclear reactors...i know of one way to make them take longer to get up to temperature. But it's also a bit messy and so i'm not sure i wanna include that. Basically, if you reduce the reactor power but then also raise the efficiency of turbines, they will take longer to increase their temperature while generating the same amount of power, but any other (modded) entities using steam turbines will be affected and break their balancing.

Well on the other end of spectrum is, keep steam generators pushing/using all the power, all the time. Only 2 settings on your coal/nuclear plant full blast or off. Anyways :) don't stress, like I said, just spitballing here..

But there is no such setting in vanilla. Steam engines adjust themselves to load. You have to implement it through very weird script shenanigans - the only thing i can think of how to do it would be to add an invisible nuclear reactor because those do always run and then hook that up to the steam engines etc but yeah it'd be a mess. And while probably technically possible, as said all the scripts will have a bad performance impact.

I'm forced to ask, why they want to "force" the Electric system to be so ... magically working and zero effort. This is something I hate about in games that implement electricity Oxygen Not included tries it's very best and is pretty nice, but fails, Stationeers is a mess, Space engineers also don't really have a system. Minecraft mods have the best in game Electricity system ;D Ic2, well so laggy not playable.

That's because factorio is extremely well optimised. You want more features? Those will cost performance for the game even when you're not actively using those features. It costs effort and bloats the code base to make it run in more general cases instead of the specific case the devs made them for.