Global repositioning/resizing of 2D apps & more 'Oculus TV' features
It's painfully obvious that the Go's primary selling point is its media playback capabilities. I can't be the only one who uses it as a virtual TV screen for private viewings of apps like YouTube, Netflix and Hulu whilst in bed. I think it would be a real boon to this if the Go OS had global features for repositioning/resizing the screen, as the YouTube VR app has.
It would be great to be able to quickly grab the screen of whatever media is being played and move/resize/rotate it, or even lock it to your gaze direction. It would also be great if the 'Oculus TV' app that a lot of us use to watch media had these options with more customisability of your viewing environment, such as dimming the lights or downloading your own environments. Some third-party apps like YouTubeVR and Skybox already have these features so it'd be great to see what Oculus could come up with.