I love the idea of an ocean base because I have a base anyone can see and steal from me easily but with this I can go to the ocean a couple thousand blocks away and hide there.
For the modern base: your stairs are L shaped but you completed the square by adding the garden. try cutting out the square from the sealing aswell, that way you connect the 2 stories visually and you dont use the space anyway. To further enhance this, you could let your tree grow up into the 2nd story. lastly add a sky light to the roof above the stairs. might fix the emptyness problem. I love the pirate base btw.
I particularly dig the villas. I'm designing some colorful Italian villas to upgrade a savanna village in my world and hide an iron farm/trading hall across the way from it. There's gonna be a bridge covered in buildings inspired by the Ponte Vecchio bridge too. Majority of the villagers will live there. It's my first really big project, and I have lots of stuff I'm still doing to even get ready to start it. (Like trying to get full enchanted netherite before the update 😅)