1. beautifulness (why not beauty?) => I simply feel “beautifulness” echoes the first two “beautiful”, making a point there.
2. inside and outside => We come back to this one when you know why it is wired.
3. I liked to play vs. I liked playing => It is a personal choice. There is no difference in meaning.
4. At (insert "the")beginning => yes, need a “the”
5. “had left” to “left”=> “had left” slightly emphasize consequence.
6. half (insert "an") => yes, need “an” there. I guess I keep losing “an” when I speak the sentence.
7. with top one’s peel neatly removed(not wrong, but I would use"with the top one neatly peeled") => I thought about that and then I decided to go an extra mile to emphasize. Or maybe it is my imagination. I saw such an expression in a novel, and thought the author must want to emphasize the effort being made.