I think you have a fairly good idea in general but I don't see how it would make things any "better" so to speak.
The reason for current incarnation of the brand split was because there was just too much talent to try to cram into both shows. By dividing up the talent amongst RAW and Smackdown, you're giving people opportunities that otherwise wouldn't have opportunities.
Take the women for example. You put them all on one show and what do you do with someone like Carmella? Even Alexa or Nattie? You're gonna have Charlotte, Sasha, Bayley, Nia Jax and probably Becky if we're talking all one division but then beyond that, how do you find the time for the other women? That was the problem in the first place.