After further social media digging, I have determined the following:
6A:
Alvin - 1
Shadow Creek - 1
Clear Brook - 1
Clear Lake - 1
Dickinson - 1
5A:
Manvel - 1
Angleton - 1
Ball - 2
Santa Fe - 1
Texas City (NV) - 1
4A:
Iowa Colony - 1
Can't find anything on Brazoswood, Clear Creek, Clear Falls, Clear Springs, or Friendswood
Looks like the BOA McAllen list hasn't been updated since the schedule came out, there's been a few additions and subtractions such as +PSJA Southwest and -Los Fresnos at a glance
It looks like an outdated list was submitted for Golden Triangle Classic, I submitted the most updated one that was released with the schedule earlier today
My Top 10 (alphabetical order):
Cedar Ridge
Claudia Taylor Johnson
Dripping Springs
James Bowie
McNeil
New Braunfels
Ronald Reagan
Round Rock
Westwood
Winston Churchill
Other bands that I think could sneak in include Harker Heights, Midway, and Weiss