I would have to agree with you on your two cents. Its really complicated because any type of stereotyping is going to be perceived as negative in one way or another. So with a series like Hetalia or any other personification of a nation there is always going to be nay-says and then the ones who would agree.

Like: Well America is not always so positive / Or: American is positively portrayed due to the roots of its creation. It was a nation created off of the idea of freedom and therefore he is happy to have his freedom.

Simplistic, but it can be argued either way?