No you don't. Want this, I mean.
Well, maybe you do. You just don't know you don't yet.
HMD's are a cool concept. Your cell phone (smart phone preferably) is a far better instrument then an HMD at this juncture in time. However if you want to play in that arena, then go ahead. There are plenty of solutions for doing so out there right now if you have the money.
But in reality you begin to realize what you are doing is skimming the surface of an entirely different realm called 'pervasive computing'. That is where the really cool stuff is at. That is what drives your HMD (or other output or interactive systems) then puts the cool stuff in front of you in the ways the 'augmented reality' does.
And yet, go figure, my cell phone does all of this right now, in a high powered, long battery life (relatively speaking) platform. It can tell me where I am, it can remember things for me (but cant tell me who someone is just by a photo), and it makes for a superb remote commnications platform with direct access to the internet. These were all the "that would be so cool" ideas we all wanted to do back 9 years ago when I bought my first HMD and started dabbling in wearable computing. All the hardware, the HMD, the batteries to drive it all, the ugly cabling holding it all together, has all been surpassed by a small 2 inch by 4 inch brick with far more horse power and a cool color screen. And I can hold it in front of my face and see what is beyond it as I walk down the street (Well, I hear there is an APP for that). And it costs a hell of a lot less then a single low resolution HMD.
However, if your want to get into the research side of pervasive computing and augmented reality, then an HMD is a great starting point. Once you have it in front of your face you begin to see (or not see) what it is really good for and even ways it can be leveraged. Once you understand this box, you can step out of it and see the even larger world around you and how the HMD can be used to enhance this world. Or even further, how to enhance this world without the need for a head mounted display and the limits it brings.
I already have most of what you want in the palm of my hand, paid less then what you will for your dream and will throw it away in less then three years.
But sure, go get your HMD and start working on the dream. You could get rich along the way if you can figure out how to fulfill your list and at the same time figure out how to market it. Before there is an App for that of course.