cant compare gen to gen since styling has changed a lot and many werent at their peak at the same timeframe
1st gen :
idk tbh i was barely born
I'll just say from old vids I've seen
Heejin ( baby vox )
cant judge the rest
2nd gen :
Tiffany
Dara
3rd gen :
4th gen :
dont really know enough to comment
maybe a special mention