I know the idea of mounts were scrapped for now due to issues with speed and how the world is built. But mounts that go at character sprinting speed would be nice enough. If they can just go on without losing stamina they would not need to be faster to be useful.
Also beasts of burden that just follow you - like the proposed carrying thrall would be cool.
Maybe start with a goat (preferably wearing packs) as the first tier, then a donkey, a camel and an elephant as the max carrier