Realistically nuclear power plants have two major issues holding it back
Safety
Disposal
A meltdown of a nuclear powerplant is catastrophic. They're rare and unlikely. But they still happen they are near irreversible. There have been leaps in the safety of nuclear power plants, but public perception as well as guaranteed safety are very low. This needs to be addressed. Its safe, but it's like the danger of an airplane crash. Rare, but it's a guaranteed death.
Disposal might actually be closer to being fixed than ever. If Elon Musk's self landing rockets can cut down space mission expenses, then dumping nuclear waste on the moon or into the sun or something might be a viable option.
Otherwise nuclear power has an insane amount of power efficiency. But it's dangerous and leaves radioactive waste.
Fixing these issues is vital to a Nuclear Powered future.