Carrie's back from her family reunion, so maybe she'll chime in.
Her main issue has been the bite stoppers more than anything. She was never really a big consumer of most of the "forbidden fruit" foods, so giving them up hasn't been much of an issue. She definitely tends toward softer foods most of the time, and has basically given up on our normal low-carb lifestyle while she's in braces. She eats a lot of mac-n-cheese, Ramen, pasta, refried beans, soft stuff like that. Surprisingly, she's had no problems with bread, and can eat pizza, eggs benedict, etc. She also has no problem with her favorite Taco Bell meal of a Mexican pizza.
The puffy Cheetos, though. Oh man. She literally won't even eat them when anyone else is around. That and salad. She hates how all that gets caught in her braces.
Like I said, palate of a 12 year old!