Gonna put this list together.
I'm only going to list the positions that need to be filled. Some of these only need one position filled, some have multiple slots.
Warrior (6 spots) Warriors are the protectors of the herd, first to the frontlines if an invaders show up. They are have a high rank in the herd, but only a few herd members are qualified enough to hold the position. The toughest herd members are usually the ones to become warriors, but a few have gained renown in this rank as strategist rather than fighters.
Lorekeeper (1 spot) The Lorekeeper is one of the highest ranks in the herd without actually ruling the herd. They are responsible for keeping the stories and traditions alive for their herd and ensuring the foals learn who they are. Often they are advisors for the herd leaders as well, having a great knowledge bank to pull experience and lessons from.
Shaman (2 spots) Shaman work closely with the Lorekeeper in upholding the traditions of the herd. They are responsible for leading the ceremonies and inducting new members into the herd, mentoring them through their probationary period.
Foal-watcher (1 spot) This herd member is responsible not only for minding the foals to keep them safe, but also for educating them in the ways of the herd, save for beliefs and traditions which are handled by the Lorekeeper. The Foal-watcher's main role is almost a surrogate parent and confidant for the young members of the herd, helping raise them to be productive future members.
Hunter/Fisher/Gatherer (2 of each spot) These herd members are responsible for supplying the groceries. Hunters and sometimes Fishers can assist Warriors if needed, but their main role are to be providers. Likewise, the Gatherers can assist the Shaman, but they are still providers. These members will have to keep track of any game or plants in the area that can be a sufficient food source for the herd without depleting the stock. They might be able to learn to cultivate plants or find ways to keep animals and fish healthy and well-stocked so the herd can comfortably remain in its territory without needing to wander in search of food.
Explorer (2 spots) This member patrols the territory and beyond to keep the perimeter safe and also find interesting locations, items, or even other Soquili that might benefit the herd. It is not uncommon for them to bring home a stray horse to introduce them to the herd.