I hated every minute of when my kids did youth sports. Soccer and baseball. I had no expectations of "premier" sports leagues, just fun. It did nothing but cut into my family time and expected parents to be at beck and call for transportation, as well as no regard for working mothers. Maybe this sounds selfish, but I was happy when they stopped. DS #1 was a very good baseball player; he went through grade six on a town team and then quit before he had to join something more intense. Band became more important. But the band parents were just as bad, in their own way. I went to all of the football games to see him march, and the concerts, but I did not spend endless Saturday evenings at the competitions. These people were truly living through their kids.
I didn't go to many races when DS #2 started competing. DH did it all. He started driving himself to races right around the time I started riding, so I became a little more interested. But, the parents were still somewhat "intense," although it was better.
If you love coaching, do it. But be careful.