But the relational model from the very beginning was about abstracting the concerns about how, exactly, those relaltions are supposed to be implemented/stored, and concentrating more on the conceptual API for querying.
If it were true 6NF than no, you don’t need to order, you need to make sure your naming conventions are on point.
`id` is good. `manager_id` is good. `parent_id` a little less so but still practical when abstracting away the business vernacular from the logical problem.
Other than that, everything was good. Attributes vs links trip up even the most seasoned devs. If you have a grouping of 3 or more attributes that relate, consider making it a link and splitting it off into its own table, normalizing your data further.