LA is awesome, so much to see and so. Loads of cool mid century architecture if you are into that - Frank lloyd Wright, Neutra, Lautner etc.
The California Science centre has a Space Shuttle AND Blackbird if you are into aviation.
Getty is an amazing museum, as much for the architecture and the grounds as the exhibits.
LACMA also very good.
Bel Air, Beverley hills etc is lols to drive through and gawp at all the hideous McMansions etc.
Driving is shit but necessary for most places through. Venice to Silverlake for example will probably take at least an hour.