like the pocket doors- glass doors maybe a good idea from the great room to the 4 season porch to let the most light in. For even more light maybe fixed glass doors/windows on either side.
Doret Schulkes Interieurarchitecten bni (Project) glass and metal doors
Staircase inspiration---Off Black by Farrow & Ball. Cumberland Terrace in Fort Greene, Brooklyn by Elizabeth Roberts/Ensemble Architecture