So far you sound like you should be fine. Your great step score will get you interviews. You just need to do well on away rotations and get some solid LOR's. If you do well on interviews you should be set. Just remember, there are people with 260's who don't match because of personality. Ortho attracts a different kind of person. If you appear to be someone who is doing ortho just because they have the "numbers" and why not, that will come out in the interview. So in short you should be fine, just work hard this summer and a research year might be a waste of time, after all you can do the research year if you don't make it the first time around. As far as rotations and aways, I say do one at home, one at a place you feel you are a bit overqualified for, and one that might be a bit out of reach.
There is actually an article by the Mayo Clinic that proposes a system for evaluating prospective residents, check it out, at least it will give you an idea of what some programs are looking for.
