So you want a field in you Inspector that has sub fields. Its sole purpose is to just be a bucket of data, but you have no real need to share it between classes in Unity or have it be universal in any way.
Sounds like a good use for the C# struct, right?
Nah. Unity doesn’t roll that way. You want a plain old class. No inheriting from MonoBehavior nor ScriptableObject. Just decorate that bad boy with [System.Serializable].
Wait, Unity’s default code files don’t include System? I suppose I can see why, as I haven’t noticed ’til now, but years of working with XNA/Monogame led me to not see that coming…
Do consider, however, whether a ScriptableObject might not be right for you.
Logic Monkey Media 