Did you ever feel like using Unity's SceneManager and loading levels by their scene names is dirty? I mean, that definitely creates a tight coupling between your code and your scene names. Well, I did, so I made this little system that allows you to create LevelLoader ScriptableObjects in which to define level sets. Then, you can make the LevelLoader load a specific level by specifying the name of the level set it belongs to and its index, or load levels from the default level set.
Note that this feature is still in development. For now, you can only define one level set — the default levels.