The house is a splendid example of a classical building. It is certainly a good thing to preserve it in its external aspect because in this way its historical, cultural and commercial value will increase in the future. Internally the project i believe it responds the demands and, from the distribution point of view, allows you to meet your needs, getting all the spaces. I have also proposed a alternative in the distribution of furniture at level 0, which you will appreciate.
at level -1 i got the spaces to allow your relatives to stay even at the same time, maintaining their privacy.
At the +1 level i created a large master bedroom connected to a walk-in closet and a private bathroom with jacuzzi. This room has a living room to allow you to relax with your wife. I also got 2 other rooms with 2 other bathrooms available.
Consider that for a project well done on such a precious building it would be good to get a better relief and get more detailed information, as well as to better agree with you the style to pursue and the details that make you more pleased.
Anyway, congratulations for the beautiful purchase and best wishes for the work.