Universal Hollywood is fine with one park since all of the filming and TV production is still needed for Universal Pictures. Super Nintendo World would without a shadow of a doubt be a land, but it really needs to have rides and restaurants with Nintendo's own different universe.
Yeah, that depends, but realize that the land is gonna be called "Super Nintendo World", not "Super Mario Land". Currently, Hollywood has a limited amount of space so it's tough to balance out the park with the needs of the studio and the Studio Tour since that lower lot is so close to the studio that is running currently. Unless Universal Hollywood is going to demolish more buildings and sets, which would limit film and TV production, then we're going to have to accept the fact it will be just like Marvel Super Hero Island with rides catered to their own universe...if Mario Kart is to be at the park. It's got to live up to its name, otherwise, it'll be called Super Mario Land.