Solar with battery storage is about to be so inexpensive and rapid to deploy that perhaps 100% of new capacity should be added this way.
Start with the solar arrays and then add the batteries. They will add to the max immediately. While you are deploying the solar, batteries will improve.
With batteries, you can use solar power even at night.
Lithium batteries are already cheap enough. Sodium is going to be even cheaper and much safer to boot.