If both parents and children got to choose a first school bag for the kid, the result would be very different without a doubt. While parents usually want a product that’s good for their children’s health, unicorns or racecars are generally more exciting for six-year-olds than ergonomics. Naturally, your kid should like the bag you choose for them, as proudly carrying their first satchel to school is a moment many still remember decades later. But the bag will be a big part of your child’s life from now on, loaded with books, snacks and games, and should have certain features. First and foremos…