I'm not judging you, but it sounds like you're just interested in applying to DO schools because your gpa is low. Doc is doc, so in that regard apply, but make sure that this is the right choice for you.
Also a 3.1 is low, but not out of the picture low. And you went to a very strong undergraduate program. I think with your stats you should at least get an invite from your state school. Apply allopathic, apply wide about 20 schools (Drexel, Finch, NYMC, Albany, maybe Creighton) and like 4 DO schools.