Part of fun in seeing grown up Sheldon is that he never grew up. In a sense the young Sheldon is exact opposite. We see a kid shipping grades and launching himself into high school and becoming too old for his years
Honestly i was full of empathy for the poor kid in a world where no one understood him. The lack of an adult face representing this lost child only added to vulnerability of this child.
I did not really enjoy the world of the Young Sheldon. Since i know how it turned out for the boy later in life, there is not much to explore in future either. Also the adult Sheldon really does not get back at his tormentors, it would be impossible for the kid Sheldon to do so.
Once the series gets its regular show, it world be story of one torment after another that the kid will suffer, only to be rescued by his mother. In middle of all that the kid is also slated to loose his father.
Hope the writers of the show will prove me wrong for Sheldon is too good a character to earn his ratings on sympathy