Don't know if someone else already did that. But here is mine.
(2 reactor for testing reason. Im sure someone could come up with a standard 4 reactor design)
No combinators, deciders and such where harmed (used). Only a handful of red wires (you could use green if you prefer


The design it not optimized on efficency but to be eyepleasing (in my opinion)

eg. removing one line of heat pipes, remoing ~ about 3-4 turbines or so.
Fuel inserter only work when depleted fuel cells are taken out of the reactor on a yellow belt (enough time to get 1 new fuel in the reactor)
The empty fuel cell will only be taken out, if steam is tank is under a specific amount (currently 20k combinend in the first upper and lower tank)
-> this needs testing if it is enough to not cool to much or waste cells (maybe someone can come up with a number)
currently still in testing phase but seems to work quit well. (running "smart" for 3h or something.)