I love these kinds of questions! Thank you for asking it, @WonderFlash93!
Personally, I find myself siding with @Vroom.
In my opinion, the Hall of Justice doesn’t even have the same purpose as the Watchtower. The Hall of Justice is a humanizing place where the public knows that the superheroes meet, giving them some access and grounding living legends in reality. It’s almost like an embassy.
The Watchtower is more like a military compound. It’s designed to be inaccessible, fortified, and reserved for trusted members of the team. It’s more than a meeting place, it also monitors the planet for danger and is often a training facility for new league members.
I think that’s why I liked how it was presented at the start of Young Justice, at least outwardly. I wish the Hall of Justice had more of a purpose than just being a front for public spectacle, but it was still really fun to see both the Hall and the Watchtower in use.