Perhaps it's the word "charisma" that's making me rebel against it. It conjures up images of perfect white teeth, slicked back hair, year round tan and false promises. "Engaging" would be a better word. I can see that if someone was engaging and informed rather than just informed they'd have more success.
In all honesty charisma is a perfectly good word for it. The meaning of the word is just right for the context. In fact it's wrong to say charisma is white teeth and slicked back hair, orange tan and false promises. They might be what a charismatic con-man is like to you... and they don't preclude it.