This goes for yesterday, so your mileage may vary with it, but I was late to park and got in line to enter at about 4:50, gates opened around 5:26, I hung back on the lower lot and lined up for Legends Collide, since not many people were at the time, managed to get that done right when it opened around 6:20 (Word of warning, a ton of scares were missing and I had a much much better run later in the night when it was dark).
Headed straight to the upper lot, Curious George opened roughly 6:45, was among the first into Halloween a little after 7, and went right into scarecrow with no wait, hit Hotel, then La Llorona (point of note is even when La Llorona is listed at a 30 minute wait time or more, so long as the end of the line is visibly still on the street of Pets Place and not stretched into Despicable Me, your wait is likely lower than listed), then Blumhouse and tram.
This was where the major halt in this plan comes in. It was still relatively early, I think around 9:30, and Weeknd and Klowns were both hovering around hour waits each, so how you'd choose to spend this time would probably have to be up to you, I mostly just meandered and sat around Pueblo del Terror, the Haunted Forest, and the Death Eater alley, just to kill time. I did eventually just say screw it and waited like 45 minutes for Weeknd, but didn't end up doing Klowns at all since I wasn't feeling well and had to call it a night.
Overall, it's not a terrible plan, but it does come with the massive caveat that in the end youll inevitably either need to just bunker down and wait through the klowns and weeknd lines, or you have to stay till very very closing, since I didn't see waits for Klowns or Weeknd drop until maybe 1:30 am last night.