Well, it's not wrong, but you should just say the exp per silver ratio is always 1,25 no matter the level, except in the case of the [exp] or kingdom bonus, where the exp gain doesn't increase the cost. Hence less you pay, the better ratio you have, and so, you should always exchange 10 girls of the same kingdom (including exp) or don't exchange at all.
But it's a nice FAQ overall.
Maybe you could add the fact players should ALWAYS use story girls as fodder since they are much more abondant than the other unique girls.