Yeah I'm not a fan of the New Horizons soundtrack at all really. It all feels way too loud and bombastic to me. I would have much preferred something more akin to the more mellow/peaceful tracks of Wild World. The rain music was also really disappointing to me when I first heard it, as I was hoping for the cute twinkly sounding renditions like in New Leaf.
I'm so frustrated there are no sound settings to lower/mute the music, while still being able to hear the rest of the fantastic sound design. I find myself playing with the game's audio very low most of the time because I find the music quite grating.
Though, if I could have anything, I'd love to have the option to choose between all of the previous hourly soundtracks and swap out the music as you liked. Like how Dragon Quest 11 allows you to use the Dragon Quest 8 overworld music.