I know there are a multitude of workarounds for this, but is there any "zero time display at current playhead" options?
What I mean is, let's say my playhead is at some time, like 0:4:53:08 in my main composition, but I want the time-display to be 0:00:00:00 at this point (perhaps only temporarily, as I make revisions noted by the client). Is this possible?
You can always change the composition start time in the comp settings. Otherwise a good use of the timecode effect with some basic expressions and suitable effect settings is advised. Everything else will require a proper explanation of what you are actually struggling with instead of generalized questions.