I don't think the Model S is an awful idea, quite the contrary. I just think the touchscreen is a very bad idea, and very unnecessary too. I know it looks cool, but there are no practical reasons for it and all too many issues as raised by several people already.
I think it is cheaper to produce! I really think it is equally expensive or less expensive to put a $500 computer/screen (probably closer to $300) into the dash than it is to make knobs and buttons and a radio display and have them all work properly. And I KNOW it is cheaper to design. Plus you don't have crappy 'dummy' button slots on your car (mine does). And you can add any button you want.
That being said I want physical controls for the things I use all the time WHILE DRIVING.
Lights. I turn on and off my fog lamps with conditions. My headlamps are always on (DRL are the same HIDs as my regular Headlamps) I turn them 'on' and 'off' to flash my tail lights (I actually have to pull my parking brake to turn off my headlamps when the car is on). I also have a rear fog which I also use to signal people behind me, as well as turn on in very dense fog, or heavy rain. I do this fairly often and would prefer this on a dial on the dash near my left knee. But would be happy with any physical fog/headlight/off (or DRL) selection anywhere. Brights WILL be on a stalk (not even worried about this one), almost surely the blinker stalk. I hope they are pull to flash, and pushlock to keep them on. But I can handle a toggle brights functionality.
I almost never change radio stations when driving (always on NPR/classical). I am not really a fan of opera so I will change it then. But advance preset button on the wheel would work for me, even preset buttons on the screen would work as I can handle a few minutes of opera before I need to change the channel. And I almost never change bands FM/AM. In the Tesla I might change to 'USB drive' but dealing with the file structure there it will require attention so it will be fine on the touchscreen. It will be way better than me manipulating my Zune while driving! :scared:
Volume on the wheel is nice, I have them currently. But I almost always use the knob on the dash, it is faster. Not a big deal. I do have a mute button on my wheel which I use often. But it is something that I can easily live without.
All the other knobs on my car have the finish falling off from me drumming my fingers on them. They don't actually get used.
I hope Cruise control is on a stalk. I like my VW one a lot. I don't use Cruise all that much. This WILL not be only on the screen anyway.
All in all I am not terribly concerned with manual inputs. I would really like light controls, and a volume rocker on the steering wheel and I am set. If the lights are only on the screen I guess I am rolling with all my lights all the time. I have pretty good faith Tesla will get this done in a safe and 95% (or better) convenient manner.