I like brand splits only because they keep good title picture structure.
Dynamite: World, International, Women's World, Tag
Collision: TNT, Continental, TBS, Trios
I believe you have to cater to the most casual viewer, which means someone who maybe only watches one of your shows, and it's your biggest show. So don't confuse them, don't make it so they can't follow a star, or a title picture, or an angle, because you splitting stuff up onto the secondary show. The secondary show has to be the training grounds, the level below, declining vets, stale stars, guys on the cusp, etc. You want that audience to be the more hardcore fans that are brand loyal and you've "earned". Not compromising the main show meant to draw new viewers in, by saying they will be out of the loop if they also don't commit to the B show.
The only downside is "people will complain about being on the B show", well that just shouldn't be a thing and you aren't a boss if you let that kind of atmosphere develop. If you are good at your job, you will recognize who needs to be promoted or demoted to either show, and the talent will for the most part respect that.