Without any kind of scaling on the heat transfer rate of exchangers, this just turns into 2 fans per nefastium + a bunch of plates. Would be much more interesting if exchangers transferred heat faster with upgrades. It would mean using the heat in the reactor itself to transfer heat to exchangers remotely which are then cooled by fans. That's possible with lower tiered fuel rods, but nefastium, nope. I like the idea of surrounding rods with other rods so you have to cool the whole reactor instead of just directly cooling the rods with fans. As it stands, that's not really how it works... which is disappointing.
 "Reactor Incremental"){kind=icon}