Start with a 2 reactor 160MW design:
When you need more energy, you can mirror and extend to 480 MW:
Compared to optimal setups, this wastes 4 turbines (for the 2 reactor setup) but it saves a lot of heat pipes, normal pipes, space, and especially design headache compared to most 'optimal' designs.
The current design is 'dumb', assuming nuclear fuel is cheap; you can add smarts if you want by adding a measurement tank and insertion logic. I've not tested what the heat capacity of the design is, so it might still waste fuel on very light loads with adding steam tanks or more heat pipes.