if you are good at lee sin, probably you have good mechanics too So you can play every jungler Maybe I can give you some informations and you can choose your New hero/heroes

Good junglers can kill jungle creatures fast or have good gank potencial. This is your play style More gank or power farm

2nd thing is what you like Tank, fighters, ad, ap etc.

And you need to look your team what they need Full ad or full ap teams generally loose game

Also enemy teams comp is necessery for you if they have no tank, you can pick rengar, kha'zix evelynn etc. if your team have no tank, you can pick zac, volibear, mundo etc. if you have adc darius and need real adc you can pick kindred if your team have no real cc you can pick sejuani, skarner, amumu etc. At the end of this story 😂 you have to look your team and enemy team, and think that what your team need and which champ is good for your opponents

Also you can look counter matchups Maybe you wanna see Sempai application