I hope I can explain this idea well enough.
How about if timeline could be divided into sections and you could hide the parts you are not working atm to timeline folders…
I’m working on a tv series now and I have all the episodes (8) in one project. This is to have easy acces to sounds used previously in the episodes. It would be very cool if I could hide parts of the timeline just like you can hide tracks in to folder tracks.
Then when needed, open the timeline folder to do what you need to do, then close it again.