While there have been persistent rumors about the possibility of having a new, permanent stage in that location, the park has not made any announcements.
They need to open up the plaza as they have done for the castle. Blocking the view of the theater yet again would be Imagineering malpractice.
Completely agree with comment above. Leave it open. Don't replace the stage with anything so as you walk up Hollywood Blvd, you'll have an unobstructed view of the Chinese Theater.