Newport Beach is home to some wonderful beaches, including Crystal Cove State Park, Corona Del Mar (Big Corona), Balboa Island etc.
OCMA is a great stop for a culture hot spot! As an architect-in-training, this building recently got a really beautiful facelift. It's worth noting that OCMA is right across from some South Coast Plaza, one of the largest malls on the western seaboard, and a great place to wander around.
This is a great destination for a good long walk/hike. Locals refer to it as the "Back Bay"