I think you have a couple misconceptions that could hurt your leveling speed. First off, there's no pack to be ahead of in Legion. Outside of the very first zone done as soon as the expansion launches, every zone will be fully saturated from start to finish.
Not sure what server you play on, but I play on Stormrage, and I can guarantee zones won't be dead by 5:00 AM. They'll be swarmed 24/7 for at least the first 2 weeks. It's just how it is because people level at different paces. For every person that wants to go go go at midnight, there'll be somebody just starting at 5:00 AM because they think it'll be a clever way to level competition free.