If nuclear power plants have multiple reactors then would it make sense to swap out the reactors that are at the end of their life with new reactor designs until all of the old reactors are swapped out?

Red tape is likely to be the biggest hurdle in building new power plants, so why not place the new reactors where old reactors have been already approved? The towns that have the reactors know what would happen if all of the plant goes into complete shut down.

Also, would it make sense for the feds to operate a breeder reactor to reduce the current waste stockpile?

The nuclear waste is a national concern, and maybe once we've processed all of our waste we could accept our ally's high level waste, perhaps not only it would help repair our national reputation by helping everyone address their nuclear waste issue but we could also start stock piling nuclear fuel for a rainy day.