I would go for the Beverly Hills
Venice Beach has a huge amount of homeless people living on the street many are extremely unwell (and should be in a care setting they are extremely vulnerable ) open drug taking, families with young children, people suffering from psychosis it’s really shocking. sad and depressing. In the day it’s not quite so obvious
Santa Monica is ok but again quite a number of homeless on the streets it’s really changed in a few years not for the better
Beverly Hills is the glamorous LA we tend to often think of and can get to other areas quickly. The metro is good but would avoid in the evening as it’s shelter for the many living on the streets