Help me decide. Ballet or gymnastics?

[myturn]

Have you considered calisthenics? Kind of a cross between the two.

[~Kim~]

Have you asked her what she'd prefer? Is there an option of a trial class at each/either?

[Khaleesi]

At that age it's really just for fun, I would try out Gymnastics seeing as she does Dance already.
My DD1 really enjoyed Gym as it was a broad range of activities.
Around here they have a Circus program which looks really good for kids, they might have something similar around your area