So glad you had a good cruise and that everything worked as expected. It is the little things working well (like room service) that can make the difference between a good and a bad cruise.
You "get" Carnival, the line specializes in friendliness, so I am not surprised to hear your waiter and room steward were friendly and accommodating. That is what Carnival does best, especially in its price range. Its ships are not the most elegant, but they are fun. The food is not the most gourmet, but it tastes really good.
That's Carnival - and good for them.