Wow, you're so late. Osu! is hella fun and shit, but also really fucking infuriating if you're competitive cause of the time it actually takes to git gud™ in it. Still fun nonetheless though.
Also, you can also use your keyboard and other things for much smoother movement than the mouse. I think Z X C or something are the default keys you can tap for hits and that's so much more comfortable (and easier) than clicking. And as for the mouse, you can actually hook up a drawing pad if you've one around to use instead in tandem with the keyboard for hits. Shits dope, yo.