From what I've read, part of the problem with Phil-food is that there's an abundance of packaging. Part of the problem is that the food itself is pretty bulky (pouches or cans of meat). Unfortunately, you don't get to pick your menu. It's all pre-set a year in advance (all crews eat the same stuff). You get a a food drop at 3 - 5 day intervals.
Many crews do repackage their food as soon as they get it, but as for crushing it... A lot of it isn't stuff you'd want to eat after crushing. Further, this is a "crew"-based trek. You cook and eat as a crew, and "doing your own thing" is discouraged. She may not have the option to crush her portion if she wanted to. Also, there's no saying that she will carry her own food. She may end up packing a single meal for twelve people.
So I understand her volume concerns... I'm looking at a 62 liter pack for a personal (target) base weight of about 14 pounds.
As for clothes, I agree that two sets of thermals is overkill. You do need dedicated sleep clothes, but if you need to wear the thermals as sleep clothes and occasionally as a base layer on the coldest days, I doubt they'd fault you. Just be careful with food prep when wearing those particular clothes. Any food spills and those thermals can't be slept in until they're cleaned.
You definitely DO need long pants. Some of the program events require them for participation (horseback riding, climbing, and a couple others). I plan on taking a single pair of convertible pants.
So I've jumped in a couple times without ever actually answering the original questions. I love panel loaders. After comparing (on paper) the SMD Traveler, ULA Camino, a couple McHale panel loaders, a GoLite Lite-Speed, and a couple other packs, I'm heavily leaning toward the SMD Traveler. It's light (25 ounces or 31 ounces with the optional stays), big (62 liters - huge by comparison to some), carries 30+ pound loads very well (I hope to never test that), relatively affordable, and comes from a cottage manufacturer with a very good reputation.