My must haves for pasture turnout are free access to water and shelter, fly mask and leggings when flies are out, and a grazing muzzle when grass is too rich or horse is gaining weight.
Your horse may not ever need a grazing muzzle, but always be aware of pasture conditions and monitor your horse for any unusual foot sensitivity, especially in spring and fall and any time the grass has been under stress such as drought. This is a lesson I learned the hard way. My horse used to be out 24/7, with a grazing muzzle during the day. His diet consisted entirely of what he ate grazing. In spite of this he developed laminitis one spring, and then his lifestyle had to undergo big changes. He’s too much of an easy keeper to stay out all the time, so now both my horses are stalled at night and wear grazing muzzles while they’re out during the day. Like I said, this may never be an issue for your horse but best to keep it in mind.