My fav is from 7 to 8'5. Where i perform better is 9 to 9'3. There are some AR10 stuff what is really really enjoyable to play.
Worst osu player effort/reward.
Sightreading Pass: 9/08/2018 The Big Black 10/08/2018 Lia - The Never Ending Love (DJ Shimamura's XTC Remix) 10/08/2018 Team.NEKOKAN - Airman ga Taosenai - Blown by the wind 13/08/2018 Camellia - Insecticide - [Arles AR10] 13/08/2018 GYZE - HONESTY 20/08/2018 Seiryu - AO-Infinity
Whatever fits the map really. Most the maps I like have around AR 6, because they always feel more laid back. High AR usually compensates for lots of overlaps, which can be odd to play. AR 6 is best experienced with CS 6 to me.
Depends on the object density really, but for ~4-7 maps (what I usually play), I prefer AR9-10, with the exception of if the map has high CS (4.5+), then AR9 is more comfortable.