I did an MA at an unranked large state school after doing a BA at a fairly highly ranked state school. I'm suuuuuch a better applicant now. It was funded by teaching, which was a great experience, but the number one thing I'll say is that you just need to avoid getting comfortable in the department. It's only two years, so attend conferences, submit papers for publication, apply for awards and grants and so on. If you really get after the professionalization and scholarship sides of it, it'll make you a way better candidate for PhD programs than you ever were straight out of BA.