Manufacturers have to change their design philosophy when it comes to smartphone integration and the car.
For example, BMW is of the design school that you integrate your phone into it's systems via iDrive (hence BWM apps) and you hide the phone.
Some manufacturers are starting to experiment with the approach where the phone/device becomes part of the dashboard.
Both approaches have pluses and minuses.
Note: keep in mind a lot of things you are asking BlueTooth to do is not currently possible due to its capabilities so integration via USB/Dongle/Car Dock will provide most of the function.
Also, noticed that only devices from Apple have integrated apps, it has to do with the fact apple apple provides special access/functions (APIs) when you connect your phone to the car via usb or connector.
You will be glad to hear that Apple recently had a job posting for the designer with car design experience, so it's obvious that they are interested in car/phone integration. Just the fact that Mercedes announced future integration with SIRI is a confirmation of that future.
Just based on comments here it's clear that BMW approach to phone integration is not favored by tech savvy people. We want our phone to be part of the dashboard and not hidden way.
At the end it's a difficult balance; how do you give more but with less, after all you have to maintain the balance between paying attention to the road and getting additional inputs from your phone at the same time.
If you ask me, car manufacturers have a poor track record when it comes to designing and building software, so do not expect miracles in a next 5-7 year.
The only way out is for them to oursource that part to reliable partners. But even that did not work for Ford and some people will consider MIcrosoft reliable partner (I am not one of them) (Ford touch became a big flop because Ford and Microsoft screwed up because the system they designed for Ford does not work to customer satisfaction.)
Yeah, we can dream but very little will change very soon. I bet next redesigned 3 series will still have hidden iPhone connector in a center dash. I can put my money on it. If nothing else, cup holders are the indication of how rigid BMW is to its design principals.