Very interesting, Lola!   Sleeping in a plane….is it sitting upright in a seat all night?  LOL!
And for the less adventurous, here’s two hotels in the Citta Alta portion of Bergamo that I have enjoyed, especially the Gombit Hotel!
The Gombit Hotel is a remodeled glamorous hotel adjacent to the Citta Alta Gombit Tower - a special first class experience and nicer than most of my other hotels. I splurged at this location and reserved the room with a small sitting area that has a round table & lounge sofa.  The bed was up half a flight of open stairs.
Hotel Piazza Vecchia is also very nice.  It’s more modest, but my room was very spacious with a large bathroom.  Their breakfast was also very good.  
If stairs are a problem, I will mention that the Hotel Piazza Vecchia has a steep set of stairs as you enter their front door.  The friendly staff immediately offered to carry any suitcases, but I was fine.  The Gombit Hotel only has a couple of steps, and they have a nice elevator.