plot building
characters
comic sense
descriptions
like others already said 😛 besides that two things i like abt her is that she manages to bring abt twists that actually surprise me 😆 -everytime i read them, at that(which is a lot)!! other authors are good too but u tend to get used to their style and predict the twists n turns...im used to jkrs style but im simply not able to guess the suspense bits...at the most its just a few chapters or few pages before its revealed 😆
other than that i LOVE the way she makes seemingly insignificant details extremely significant later on in the book .. for example in GoF with that skeeter cow...i hardly paid any attention to all those beetles jkr mentioned..the water beetle..the beetle on the statue..hermione slamming on something in the hospital wing..and when it was revealed i was like omg 😲..there are so many more like that,none come to ind now 😳 ...but i just love how she does it...
so yeah---i love everything abt her 😆😳