Ella, first of all not everyone likes ballroom dancing - even among those who love to dance.
Ballroom dancing includes many different dances - which are danced in different styles, tempos and moods. The ability to express your feelings of the music and dance style is great.
The ability to control your body and make it do things that seemed impossible a few years ago is nice.
The improved confidence, the image that one projects, the better posture is nice too.
But what is the best? For me it's the ability to create something with my partner together, something beautiful. To feel each other in a properly led and followed move, the flow of the movement, to know that it looks like a single mind is moving us over the floor, where individual parts of our bodies interact in harmony. And the best part of the best? I am dancing with my beloved wife of ten years.