First case will work very well.
Create a struct “SkillStats” for the raw data. It has only data. Create a component “SkillComponent” (ActorComponent or SceneComponent). Now use the “SkillStats” as a property for “SkillComponent”. You can do something like “LoadStats” in the component or just pass a already loaded “SkillStats” parameter into that component, that’s free to you.
Attach the SkillComponent to any Actor. Then you can use functions from the “SkillableActor” or directly from the component. This component reads and updates the skill stats for that one object.
Maybe create another layer like “SkillableActor”, which always has a SkillComponent attached to it and expose the use of SkillComponent to the Actor.