Depending on how you wanna handle player progression, I could also see being able to upgrade skills procedurally. So that you have the base stats, and every point you further invest into it gives a procedural stat bonus to that skill. Probably with diminishing returns (a log function or something) to prevent power creep, but that could just be a good time sink on the by, for those that want to grind out stronger skills.
But that's probably featurecreep for a later time x3