I like this idea!
I don't know if this was the intention of the OP but my issue with social spells is that you can't cast them in a conversation. Casting something like friends is rarely possible before you engage in a setpiece conversation like Kahga or an goblin encounter where conversation starts automatically and advantage could be really helpful.
I can see the need for some balance if you can give yourself advantage on every charisma roll you have to make, but that could be offset with something like a stealth skillroll to fool someone that is well versed in the arcane or a willsave from the target to signify someone with an extra strong will.
