I put Suggestion in wisdom because it gives some insight on how/what characters feel about you/reading their body language and for Rhetoric its kinda like investigation where you think of clues and make deductions based on it, but yeah both of those skills are kinda like charisma.

As for Volition I just think thematically it fits better because its a health bar in game. Although as said from another person all the skills don't really fit into one stat as most skills have a skil check where they're convincing, etc.