Firstly, with any sort of sound post work on features, don't consider a feature length project to be one single timeline.
Best practise with long-form work is to split the project into "reels". This should be done in conjunction with the picture editor. Splitting the project into reels assists with undergoing re-conform operations as there is no such thing as picture lock. Ever.
Each reel will be about 20 minutes long and will start at an Hour boundary. For example, reel 1 starts at 01:00:00:00, reel 2 starts at 02:00:00:00, reel 3 starts at 03:00:00:00 etc for as many reels as you need.
Secondly, the dialogue editors job is to edit dialogue, not mix dialogue. There may be a need to perform some basic de-noising and treatment, but this should be done in conjunction with the re-recording mixer.
It is not a good idea to split every single scene into a different track as automation can be easily used in the mix to separate mix parameters in order to match dialogue.
Remember, as a dialogue editor, your job is to edit, not mix.