I'll definitely still use it. The Spice District is the one I play the most as well, it feels busier and livelier and somehow more immersive with a lot of character, though I get irritated with the basketball court, as too many of my Sims are constantly going over there and changing clothes, even in winter.
But I see San Myshuno as a place for big city, high rise apartments, whereas some of the more suburban and rural maps would have townhouses, duplexes, small rises, and boarding houses and trailer parks. Maybe even little hut colonies in Sulani. There will be so many possibilities, I'm quite excited for this pack to change the entire dynamic of the game.
My only concern is what limitations there might be and if there is any intrusive game autonomy. But I'm really looking forward to the livestream. ☺️