I miss a lot about childhood. I miss being able to go out and play baseball in the spring and summer, football in the fall and winter and hockey in the winter.
I was not that self-conscious yet. That would come later and when it did it never stopped.
I miss relatives that were around then but are not now.
I really had a lot of worries in my childhood, so I can't miss not having any. What I miss is being able to do pull-ups, and various kinds of gymnastics, and to ride my bike for miles and miles. I miss the physical prowess that came with youth.