I think the folks who like the idea of the league, like it in general, not as something specifically run by Lavar Ball. This league will always have the advantage of paying players over NCAA regardless of possibly changing the one-and-done rule. Advertisers/sponsors would take a lot of their college money and pour it into this league. Sponsors would make sure these players would make 6 figures. How much does Nike spend on schools trying to hook the next LeBron or Curry? If they knew that next superstar would play on Nike's team in the development league, they'd move their resources there to make sure to sign that player, that he succeeds, and is popular. Right now, Nike sponsors dozens of college teams to find the next LeBron. They wouldn't move half that money in a single team of top 50 talent? Same for Adidas, sports drinks, sports agencies. Fandom is national, not local, and built in. How many here already have a strong preference in shoe brands? Sports drinks? Rivalries already naturally occur. Team Nike vs Team Adidas!
All revenue streams are open to these players. They can sign with an agent, get endorsement deals, sell jerseys, sell autographs, make personal appearances, make commercials, etc. NCAA will never allow all these things, and CBA does not address them. I think those in support of a new league are thinking way beyond what Ball is proposing. He is basically right - anything outlawed creates an alternative market. But he is too self-absorbed to see the big picture, and he is, at best, just a piece of it.
College fans will be happier with this league as well. There will be more four year players and continuity. There would still be some future NBA players (unheralded Curry types, education types), but it would no longer be the free NBA minor leagues. Academic integrity would improve. I think it is a win-win overall.