Things to consider as a surgery resident (from someone not in a surgical field):
Are there fellows? How many and how many times will they be taking your cases? Some people are just OR junkies and going some place with few, if any, fellows makes sense, even if it's not as prestigious as your other options.
What's your OR time as an intern?
Do you want to do a fellowship? Do they have a fellowship in that field?
Can you readily take time off to do a research year or two?
Are there any unique opportunities offered by the program that no one else has?
Moonlighting opportunities available? It may seem like the absolute last thing you want to do is work more, but at least having the opportunity to garner some extra cash could be useful in separating out programs.
More general things:
Location? How much fun can you have there? While it's true you can live anywhere for 5-7 years, I'll tell you from experience Chicago was way more fun than Little Rock, Arkansas (and I loved living in Little Rock).
Close to family and friends (or far away from them if need be)?
Do you have a significant other? Do they have an opinion? If not, are you going to want one? Again, Chicago was way more fun than Little Rock
Is the weather significantly better in one location or another?
What are your hobbies and does one program offer something the others don't? I kept Utah in my top 3 even though realistically it was a reach because I loved the idea of being 45 minutes from the ski slopes.
Cost of living and how well does your stipend last in said locations?
