You and I think very much alike. I've had a BlackVue 650 two camera setup in my car for some time. I've recently started driving for UberX. I have the same concerns as you. I've just yesterday moved the rear camera from the rear window to the front windscreen, looking into the car. To ease any concerns my passengers may have about being recorded, I've put the camera in front of me, not in the centre of the windscreen. I figure that I only need to confirm that I didn't do anything inappropriate and recording me should do that. The front seat passenger is still visible but only in the far side of the image. Likewise the rear seat passengers. Like you, I'm also going to be saving recordings to a hard disk for some months.
I asked Uber about video recording and their response was:
"As an independent contractor, it is your choice as to whether or not you'd like to have a camera in your car. That said, it is important that you follow local regulations regarding proper disclosure of any recording that you do, and we do find that riders tend to find being recorded an uncomfortable experience, which may impact your ratings." (My emphasis, ratings are Uber's big stick.)
Sorry, but Uber will not take such a reasonable approach.
I asked Uber about video recording and their response was:
"As an independent contractor, it is your choice as to whether or not you'd like to have a camera in your car. That said, it is important that you follow local regulations regarding proper disclosure of any recording that you do, and we do find that riders tend to find being recorded an uncomfortable experience, which may impact your ratings." (My emphasis, ratings are Uber's big stick.)