It's hard to step out of the shadow of Legion, which was utterly fantastic in almost every way, to enter an expansion where you get one item per boss in the last expansion because the rules have been changed to force more grinding, where you have to grind reputation in the old expansion that you probably skipped because rep grinds suck JUST to unlock allied races (who aren't fully unique races since they recycle old content such as animations), where questing has SOMEHOW become boring again and where your new abilities are given by items you'll swap out every level, meanwhile being only boring passive effects no one cares about.
I highly recommend actually staying in the 20-60 range zones until you ding 62. The reason for this is that despite getting a slight penalty in experience for being over-level, the advantage of having flight will more than offset this. That, and WOTLK and TBC zones are the slowest part of the leveling process. Minimizing your time there as much as possible is worthwhile.