WHY NOT VOICE COMMAND EVERYTHING. THAT SHOULD BE EASY PEEZY LEMON SQUEEZY.
Why not take off your CAPS LOCK key when posting?
And no, voice command for everything is not as easy as you think it is. Dealing with ambient noise, different accents, and free-form language parsing are all significant problems to which there is no general solution.
In the imaginary universe, you can do anything.
Voice recognition is quite a difficult problem, but in Tesla's case it wouldn't have to be free form. There's a limited set of commands that you'd need.
Both Google Now and Siri have voice recognition that are quite accurate, and both really are free form.
Siri is pretty decent, and driving directions with Siri are excellent.