While nothing new here, its well articulated. It used to drive me nuts when I was younger (twenties and thirties) how some people that seemed to lack intelligence were so successful. In fact in one corporate job I had I started a saying that anyone I mentioned to a) completely understood and b) laughed and groaned at the same time - Here at Company XYZ the "Curd Rises to the Top"

As for the crux of your post, the sooner your realize little in life will go as you "plan" the sooner your learn to be adaptive and setbacks, then become challenges to overcome rather than obstacles impeding progress. Just my thoughts after reading this … enjoyed the read