Some people call Zion the “crown jewel” of Utah’s five national parks. It certainly has the most massive mountains and most prized hiking trails. And we liked it a lot. Perhaps if we had hiked the Narrows (wading through the river) or climbed to Angels Landing (probably the most dangerous climb in the entire national park system), we would have treasured this as much as others. I would definitely come back, and the mountain sheep in the wild were a special treat. But to me, either Bryce or Arches should have the “crown jewel” title.
You would not know it, but the day started out cold and rainy, then broke to be a gorgeous warm fall day. I recommend Zion in October. I can’t imagine this would be any fun at 100 degrees and full of people.