Having just gone through the process last year as an applicant, I don't really feel qualified to say much about your GPA-- my sense is that if everything else about your application is stellar, a 3.4 is very likely not a deal-breaker, particularly if the low grades come from an unrelated subject. But the whole process is so competitive and subjective that it is difficult to generalize.
I suppose that my insight based on my own application process is that the professors with whom I spoke seemed to really know about me (I mean that they seemed to really have paid attention to my application, and to have considered it as a whole). They did not seem to care excessively about my scores and grades, although these topics did also come up in conversation, so were not ignored or totally unimportant.
But, if you're going for classical archaeology, I'd say this-- you pretty much need to have fieldwork experience for most programs, and you probably want to start working on German right away, if you haven't already. Your French minor is certainly helpful, but the more modern language preparation you have going in, the better.
I applied to around 8 schools-- mostly PhD programs, but a few MAs as well. There are several MA archaeology programs that you might want to look into rather than/ in addition to MAT programs-- Arizona, Florida, and SUNY Buffalo all come to mind. I tried to apply to a broad range of programs, with some being super-competitive, and others slightly less so. Beyond that, spend time researching schools and figuring out what programs have strengths in areas you want to study. I think this notion of 'fit' is probably the most critical part of your application. You ought to be able to articulate, for each program that you apply to, how you fit into the department intellectually. Your current professors should be able to give you direction in this research.
Good luck!