Continuing the updates, after looking at that area noticed that it uses pretty much the same materials and assets, so I decided to extend the scope, starting all the way from the entrance to the throne, up to the exit to Liurnia:
Some screenshots of the new areas:
Entrance to the throne room
Throne room
Middle of the area, this is where you find the Shabriri Grape item.
Exit of the castle into Liurnia.
The throne room has a bunch of different assets/textures, so that will take a while to finish it, also there are several statues, which will be a problem as I don't have experience with it.
Here's a video of the process of updating these areas: