You have a good point of course. But a lot of the cost of a nuclear reactor is in the safety systems. Which is being driven not my mathematics, but fear. Fear is the root cause of NIMBY. If we attributed the deaths caused by coal into the safety of mining and coal plants they would be alot more expensive too (but we don't, those are relatively hidden cost, while nuke absorbs some of those). We fear nuke power because of three relatively bad plant disasters in older style plants. Two of which are directly attributed to human error (TMI and Chernobyl) caused by improper operator commands.
I argue that we should go back to the drawing board. Do the research and get a safer design.
So to get cheap Nuke power we need:
1) Simpler safety systems as new designs incorporate safety by design rather than relying on pumps, electricity and human operators
2) Improved Training courses
3) The ultimate goal: Mass production.
Right now every plant is unique. We spend billions doing safety assesments, environmental impact studies, training, and inspecitions etc. What if we got to a design that was an appliance? Where you could get one installed next to your house, or one in every city or something?
Pebble bed reactors potentially would allow this...
Because it's not the fuel that makes nukes expensive it's the safety related stuff. And a better, newer, design might very well simplify the safety issue.