I honestly don’t know how to help with this since Blizz hides their population information now and Blizz won’t say what the indicators Full/Medium/Low mean as far as numbers (low = 5000 players etc). The closet thing to an answer in that regards that I’ve seen is
in a response about classic realms and this
but that mentions classic so I’m not sure if it applies to retail as well 
I can tell you from personal experience (i play there) that Tich which is also -7 is well populated 