Here is my current line of thinking into the background and context of the protagonist and his home, which will help fuel the designs as a whole.
My initial thoughts for the protagonist is to be of a 'coming of age' male, reflective of a pioneering spirit. Originally a farmer, he had a variety of tools and equipment at his disposal to adapt to the flooded world. But now alone and isolated, he roams the skies in search for land and signs of any other survivors. Additional thoughts for details include props such as a telescope to pouches.
The home of the protagonist has been adapted to power and maintain the flight of the island. With limited space on the island, the modifications also serve to maximise the space of the house. As such, initial impressions of the house are of a quirky design with a variety of different materials the protagonist would have managed to collect in his travels.
Identifying the system which keeps the house and island in flight will be key to the logic and design of the home as a whole, which I'll dedicate and post to later with more research.