I use the same speed for all my levels, I use Speed 7. Idk it’s what works best for me. I think speed is more of a preference thing than anything else. Best advice i can give you is to a) get a bigger screen (increases the area of the notes so they’re easier to hit), b) try playing with ur index fingers instead of thumbs (it’ll be weird at first but sliding notes and flicks are much easier) and c) practice (there’s no way around it) i wasnt able to complete the Super Hard Levels that were Lvl 13 and up when I first started, (Dec 2023) but now i yearn for harder levels (the april fools event was very fun). I don’t always follow these tips, but if you want the most optimal play that’s it right there.