Visible Handheld & AR Keyframes

I really love using the handheld feature on mobile devices, however I want to be able to have this on PC or Mac as well. So the suggestion I have is the ability to use your mouse or trackpad to move around the camera in realtime & record its tracking, just like the gyroscope of mobile devices

When animating complicated scenes with parallel actions in different parts of the set, I found myself needing to set the animation right linearly, as I moved on, in every part of the scene, because going back for adjustments in the timing was very difficult. If I miscalculated the duration of the parallel action and needed to slide down the timeline a complicated animation with multiple characters, I found I had to slide one by one each keyframe from each character. I would stick to the screen a strip of paper where I could mark with a pencil the relative positions of the keyframes, so that I could quickly arrange them again at their new placement on the timeline, but there's got to be a better way of doing this. If we could only select batches of keyframes and slide them together up and down the timeline, that would really help make corrections, even if we had to do it one character at a time. If we could do it for multiple characters that would be even more helpful.

this must be possible? it seems like it should be since camera movement is a fundamental aspect of film making and this key-frame issue also spills into character and object animation. currently the key-frame slider option to create more or less ease doesn't change a thing. i'm trying to previs a commercial but have had to give up because i can't produce a simple camera move without ease messing with the pan, tilt and camera speed. any added key-frames to fight the 'ease' create even more bumps in the movement. been using this app for 4 years and you guys had it right at some point. but for a long time now, whenever there is a pan and tilt the ease over compensates and there's no way to control it.