"Well... becoming a star sounds interesting, but i'd like to become a planet instead." you tell her.
"Alright then, what planet would you like to be?" Remember, you can be anything you want, I can even make you into a new planet. Just go with what you'd like the most.
"Uhm... sorry if I sound shy, it's just that i'm a bit scared about becoming such a thing..." you say in a weak voice.
"Well, Master... as the transformation completes, your mind will adapt to being a planet, and will likely change a lot. Of course, planets don't think, so I don't know exactly how it would change. Although I can assure you, your mind may change, but it will never fade away. And... I forgot to told you one thing: all of my granted wishes have a happy outcome. Even if you want to become the ruler of everything, you won't be evil or go crazy of power... and in the end, everything will be better than before." she explains.
This gets you convinced. You want to become...