I enjoy reading books on self improvement the last book being "The 5am Club". I also enjoy novels such as the "Pianist of Yarmouk".
Advice to past self
Don’t get engrossed in the academics… Ensure you have sufficient balance between work and play.
A historical figure as imaginary friend
My imaginary friend would be Heraclitus because of his views on the world and how everything is in a constant flux. His famous saying is that "you never step in the same river twice".