Here some ideas, others that they might actually write, others they might just think.
I wish every elf, who ever visits this town, would have to live for year as a human.
I wish to be able to stydy wizardy
I wish I could visit biggest mountain in the land
I wish my father would have his old job back
I wish have a new set of winter clothes
I wish everyone here could give me birthday gift my next birthday
I wish I could fly
I wish I could read thoughts
I wish that everyone would love me
I wish I could understand every language
I wish people would stop lying
I wish for nothing
I wish we have happiest festival this year
I wish I was smarter
I wish I had little brother or sister
I wish to see a god (by curious child)
I wish to find my true love
I wish my life would become really interesting ((my one character said this accidentally while wearing ring of wishes, bad memories, bad, bad memories))
I wish I could be king/queen for a day
I wish everyone was always happy
I wish everyone would be more like me
I wish I had had sister instead of a brother (or vice versa)
I wish my cat would never die (some kid of her dear pet)
I wish I had dragon (or other monster or big wild animal) for a pet
I wish to have a new house