Perhaps the idea could be expanded even further and there could be an upper section like we currently have for busses, also similar in functionality to what MS Word has, eg:
(hopefully that image works and there's no hotlink protection)
So what you could do is drag a bar down from the top of the screen, just under where the video track would be if you choose to show it, and it would split the screen into two, and you could put as many tracks in the top pane as you like where they'd stay put, and leave the main pane for scrolling.
Expanding on that, why not do away with the buss paradigm altogether now that we're getting track to track routing, and rather than having a buss pane at the bottom, just have another custom pane you can drag up and you could put whatever you like in there, basically replicating the separate buss system now if you choose, or putting tracks in there or whatever. Having three separate custom panes where you could split the view however you want would give you HUGE visual flexibility!
But failing this wacky idea, the initial sticky tracks suggestion is also pretty great. I'd definitely find that useful!