Big surprise: my top 5 will definitely include some "modern" albums of the 2000s.

Sorry to break the trend of older albums. But you knew it was coming, Marian.
I'll try to provide an answer to your question about sweet bands, and Lena and Harry can add more later. At Fans Reunited, Harry told me that he loves the music by the hotel bands. But they can also be referred to as sweet bands. I believe the term started with Sammy Kaye's Orchestra who was referred to as playing "the sweetest music this side of heaven" (or something like that). Other sweet bands were: Kay Kyser, Blue Barron, Ozzie Nelson, Russ Morgan, Ted Weems, Ray Noble, Eddy Duchin, and my favourite band name ever: Glen Gray and the Casa Loma Orchestra. (This conjures up nights of glamourous women, subdued lighting, palm trees ...). Perhaps the most famous was Guy Lombardo and his Royal Canadians.
The sweet bands played melodic music with usually simple rhythms, in contrast to the authentic jazz and swing bands (Artie Shaw, Louis Armstrong, Chick Webb, Panama Francis, Count Basie, Dizzy Gillepsie, Benny Goodman, etc.). Glenn Miller was a combination of both sweet and swing/jazz. I feel my favourite band Larry Clinton is also a combination, but some place him in the sweet band category.