It's surprising that Orinda/Lafayette are comparatively cheap now. They've been historically expensive places to live, they've each got good Bart stations, easy access, safety, and access to good food. But, people seem to ignore Lamorinda when looking for a place.
Well, the jobs/money are in the Valley and East Bay is a pretty long commute down there. If all the jobs were packed into SF, then everyone would live in the East Bay. East Bay is far nicer than much of San Jose & Silicon Valley IMO with the BART benefit.
It's pathetic that the technology hub of the world has piss poor infrastructure. It's a testament to the mediocrity of the California and US federal governments. The tax revenues generated there all flow outward to subsidize regressive states instead of investing into the place that shoulders much of the load of the economy.
$/sqft factored by apartment size results in a greater uniformity of rental pricing than would be immediately apparent. With few exceptions, the higher-cost areas will have smaller apartments generally catering to singles / childless couples, while families are driven to more to the periphery. Atherton and Stanford would be notable exceptions, as both include sizeable parcels (though how many of these are available as rentals is another question).