Music is very important to me and something I'm quite particular about. I'm the same way about sound effects, but that's a different topic. I chose that music for Scott because it kind of reminds me of the Magnum P.I theme. Scott is a "guitar" kind of guy stuck in a decade dominated by synthesizer music and of course as you say, it's a way more bombastic piece than any of the other music in the game, which suits him. For the front yard Christmas music, I wanted something that sounded like the song Snowcloak from the FFXIV OST. I'm not sure if I succeeded, but for veteran players, I wanted a piece of music that hits you when you walk out into the front yard when you're used to the normal exterior scenes.
As far as other holiday events, I programmed in several possible holidays, including Mother's Day and Halloween. Halloween is a no-brainer and often expected for a game like this since it's an opportunity to put characters in different costumes.
I'm hoping Nicole will get her own update sometime next year. If Jasmine gets any content, it will likely be as part of a Brooke update.
Cheers, Merry Christmas & Happy New Year!