Agreed. However, adding a single CAN bus ADC to the fuse PCB (to sense no voltage on circuits with a blown fuse) would cost almost nothing, and would allow the computer to provide information on the blown fuse and instructions on how to replace it. IMHO, breakers = expensive needless feature creep, but user feedback = welcome to 2015.
EDIT: I was thinking of the 12V accessory fuses. In light of the reply from Tesla, I can imagine where if the drivetrain fuse blew you might not want an average user replacing it ... and I imagine that for something like that, it probably already throws a code that gives you an idea of what's wrong.