Thank you all for responding! It's been helpful to read how you've thought through things.
That's awesome that you got funding! I got an offer that would cover tuition and enrollment fees, but I'm still worried the cost of living in the area will be prohibitive...
Those are all great reasons, and they really mirror my own thinking. On the other hand, I have also thought that for sociology at least, many schools accept students directly from undergrad. In some sense, I feel like the standard is lower for these types of applicants (for example, you wouldn't expect an undergrad to have published something in a reputable journal or have travelled to a conference), whereas for a masters, those qualifications become the norm once you move on to the PhD. I definitely also feel that I'm underqualified in terms of methodology, but all phd programs include that type of specific training. I just don't know how much more competitive you really become with the masters, not to mention that it's one or two extra years on top of the 5 min. required to complete PhD in the social sciences in the US.
I'm just playing devil's advocate to see if others have thought about and resolved the same doubts that I have.
Victorydance, my advisor here has warned me against UT's MA! One of her best friends is one of the 7 latin americanists in the Gov't dep't that you've mentioned, and she has told me that there's currently a pretty large disconnect between the two programs. I spoke with her and was told that LLILAS is is very disorganized (to the point that she hasn't been in communication with them for a while) and has a heavy bias towards critical anthropology that has alienated her and other profs. I was really disappointed to hear this, since LLILAS is such an amazing resource (half my library books for my current thesis are from UT), and I applied anyway just to see what would happen, but I don't think I'll go given the lack of funding.
Of course, this is just one professor's opinion (and very possibly, an unfounded grudge!), but it might be worth reaching out to make sure that you'll be able to have the kind of contact with the comparative politics profs that you're hoping for before you commit!