Pumped storage requires very specific geography and how much energy can be stored is very dependant on height differences. It is also only 70-80% efficient. Compressed-air energy storage also requires specific geography. Molten salt is not going to be a great idea in places that have lots of wind, but not a lot of sun (UK in winter for example).

To replace strip mined coal burning generators and fracked gas we need a mix of just about everything.