Concerning the design of the bikes, I think there is still room for improvement. The designers can look at the design of the Public Transportation Bike ("OV-Fiets") in the Netherlands[1] which was a major success in a country where there already were more bikes than people before it's introduction.

For a bike that is available 24 you would want a bicycle lamp on the front with a dynamo instead of just reflectors. This is a safety concern because reflectors have proven to be unreliable to signal other road users.

The bike doesn't have any mudguards but I suspect the weather in SF allows that :).

The carrier on the back wheel doesn't look that sturdy and there is a large gap in the middle. A front rack to place heavier cargo on could be a benefit.

What about bright colors so the bike stands out?

[1]http://www.ov-fiets.nl/binaries/content/gallery/OV-fiets/nie...