Like most things in life, it's all about balance. An applicant with below average numbers usually has to make up for this by being stronger in other areas. So being AOA, if possible helps. Publications help. Honoring as many rotations does as well. In ophtho especially, letters of recommendations and connections matters a lot. If your home program has an ophtho program, make every effort to speak to the chairman/program director. Make your interest in ophtho known to them, ask for advice about what things you can do to better your chances. Show as much facetime as possible so they know who you are. Your best chances are probably at your home program anyway. Next I would schedule ophtho electives away at top tier programs, work my butt off and try to get letters from well known faculty members. Ophtho is a small field and name recognition carries a lot of weight. Schedule these electives early, as spots can fill up quickly, aiming for electives before August. August is okay, but you probably won't be able to get a letter in time to include with your application. Good luck.