Thank you for posting this interesting project! I liked working on it.
Please find my simple yet functional design below.
The fireplace is the centre of the ground floor area. It separates the study/work nook from the living/dining area. I put one of the storages under the stairs to use as much of space as possible. Both the kitchen and the living room has direct access to the veranda.
The top floor has enough space for the bedrooms and the family bathroom.
I attached some photos of a doghouse I designed. I hope you like it.