A feature request for something I will probably never use I'd love to implement, but I've never used typescript and I'm fairly certain I'd just break things.
You can already adjust zoom with the mouse wheel, but this only lets you take large "steps". A slider, whether it be in a side menu or always on screen, could allow for easier zooming for the user. Bonus points if you can type out the exact percentage you'd like to view the map at.