One of the better innovations in cars - the head-up display

I have been talking a lot about all the things that make driving more boring or create distraction for the driver. But there's one innovation in modern cars that I really like - the head-up display. When I search for a 5-series BMW this was a requirement high up on my list. And I loved it from the the first day on. The head-up display gives you your current speed or the direction (arrow) you need to take to reach your destination. And you can see all of this without taking your eyes from the street. This is really practical and increases road safety I think. However there are a number of things I wasn't fully happy with. Firstly, you couldn't program that thing. I would have loved to also see the current gear for example or the ABS indicator. Secondly, I can't understand why it's only available with the 5-series but not with the 3-series I bought after. And thirdly and most importantly, I don't understand why you have to pay more than 1'800 USD for this feature and even have to take an automatic air condition with it on top. The cost to produce the TFT screen unit and the controlling computer must be close to or lower than 200 USD, so everything else is margin for BMW? Isn't there a thing like price elasticity? Wouldn't they be able to sell 100% or 300% more of these units if they offered them cheaper?
And last but not least, if you would design a car with a head-up display in mind the whole dashboard could be structured and modelled very differently. So, here again, is a great chance to come up with something new and different. Go for it!