Hello, you have a nice and beautiful house with wonderful furniture. I suggest the first floor to split in two-unit and the second floor to another unit. I also consider a new sliding glass door for making private for the second floor and their own access but in glass that beautiful staircase might be seen. I tried to use the previous doors and wall with minimum changes .and put the kitchen and bathroom next together to not have trouble with piping. I hope you love it. if you have any other questions or added information or any help I am available. thank you.