Finished this massive custom wall on an SMP. What would you build inside

Hey everyone,

So I just finished this huge layered wall project, but now I'm staring at this giant empty valley inside and I'm completely stuck on what to do next.

For context, it's right next to a coastal town with a lot of wood and teal/prismarine roofs (you can see a bit of it on the left). I want this walled area to have its own unique vibe, but ideally still fit a somewhat peaceful fantasy theme.

I'm debating a few options:

• A custom village that uses the terrain and height differences. (I find organic villages a bit easier to build tbh).
• One giant, imposing castle in the center. (I struggle a bit with designing huge mega-structures, but it could look awesome).
• A magical forest, hanging gardens, or something completely different?

Also, I'm unsure about the wall itself. Should I add watchtowers to the corners, or does that make it look too militaristic? I kind of like the "peaceful magical barrier" look it has right now without them, but I'm open to anything.

What would you guys build in here? Any ideas, themes, or even lore suggestions would be hugely appreciated!