I have one Final Cut Pro timeline for each project. I add sources to that timeline. I go over and over the timeline again and again refining it and moving things to their rightful place. Luckily I know the films back to front and and able to retain all of the edits I've done so far in my head. So as soon as something new appears, I know pretty much where to put it. The onus is always on getting the maximum amount of source material in there without cluttering too much.
I am back from China and now in Spain. Hopefully on my return next week I will investigate the chances of getting my drive recovered. Keep your fingers crossed.
JD