Nuclear subs and carriers produce a fraction of the power of a commercial nuclear power plant.

I'm not sure why that matters? Salt water is salt water. An carrier's brake horsepower is ~200MW, so a fraction, but a reasonable fraction. When San Diego had a county-wide power outage in 2011, the carriers at North Island pushed power to the grid to support essential services.

smaller-size systems along with less budgetary oversight means higher maintenance costs are less likely to be problematic.