I'm kind of the odd man out on organizing precancels. I collect stamps first and foremost, I collect issues in as many formats as I can. Sheet, Plate Bloc, P#Single, single, etc. mint, used, booklet panes, coil strips depending on the issue and how it was made available.
I don't concentrate on cancels but I have a huge collection of precancels that I have organized in my albums by issue, in the pages immediately following that issue in my albums. They are organized by issue, then state and city. Integrated all the way through my albums Likewise with Perfins by issue.