We've been there a few times. My husband's a keen photographer so it's his idea of heaven. It really is a beautiful place and I would recommend a visit. Why not stop there for a couple of nights? That would give you time to see most of it. I'm trying to remember the name of the hotel we last stayed at - it was horrible!
Time it right and you could enjoy taking part in the eruption of a super-volcano!!
Seriously, there is a volcano simmering under Yosemite that could take out half the planet if it goes off!!
Read Bill Bryson's 'A short History of Nearly Everything.'