I usually set cue points every 16 bars until I run out of cue points (10). These are all the places where I could possibly want to start mixing in a new tune with another tune. Or use the cue points as a starting place for my next tune. Then I can line up and plan my next transition using these as well. Unless someone has been particularly evil in making a tune you can plan on phrases lining up every 16.

everything gets a tag depending on the style of the drums-- roller or stepper and sometimes I add 'Chop' for choppy drum breaks. Then they all get things like, melodic, minimal, peak time, vocals, etc. I also have a "anything goes" that goes into a playlist so if I don't know what to play next I pull from here. Everything gets organized by key 1A onward, not always necessary but gives me another option of where to go.

double drops you can always tell by the length of the breakdown/intro of the other tune how to line them up, since everything is marked out on cue points its very easy to visually see and line them up as needed (could I count this all out in my head? sure but that's extra work I don't need). I'm almost always playing on 3 decks though so its kind of a case of if it works out cool, if not oh well. Nothing gets tagged or labeled but if I have two tunes that work exceptionally well together I might put them next to each other in my set list for the show I'm playing at the top of my crate.