Circuit connections are now mandatory! But on the flipside reactors don't waste fuel by overheating. Also you can't deconstruct a hot reactor easily.

I know there are probably quite a few realistic reactor mods like that, but most of them seem overly confusing and complicated to me. This one is quite intuitive to understand and vanilla friendly. You'll get how it works very quickly. No need to remake everything. Bonus point when you'll see how mining a hot reactor works.