The metal seats have pros and cons. They have them upstairs.
Pro: Look better than wood, won't break.
Con: Curved so they're hard to stand on, curve holds water when it rains. Bring a cover for when you sit down at half.
The seats are aluminum, and I've never had a problem with heat. Aluminum just doesn't get hot enough like other metals.
Just put chairbacks everywhere but the student section--but only because they stand the whole game and don't need them.