In the beginning, nuclear reactors had chambers added to increase capacity and they interacted with adjacent blocks to effect heat inside the reactor.
I was thinking of making the nuclear reactors so that they can once again be improved through the building of a reactor core type of structure, one that serves a function other than simply insulating ones base from a potential explosion. I'd like for reactors to be bigger, perhaps having steam vents that discharge steam, rather than just small components. Perhaps using blocks of fuel placed in a macro-structure in a certain way rather than ingots in a gui.
What I'm getting at is making nuclear reactors large instead of making them just machine blocks with complex gui's. I'm thinking of something like how Terrafirmacraft makes a player have to build up things to get charcoal, for example.