If she wants to stick with her Gregory. It appears that the current aka newer (on their website) Amber 34 is now 2.8 lbs. That's a bit of a shaving off the one she has. Also the Gregory Jade 33 is 2.75 lbs.
I get it. I have 3 Gregory packs myself. 2 trail running ones and the Amber 70 for backpacking. I think they are some of the best fit packs I've tried. I just hope since I bought my Amber they have fixed the water bottle pocket situation. Because my pack, it is nearly impossible to get a water bottle out of the pocket while the pack is on my back and I hate that using a water bladder is the only option. I like having choices. That being said, I think my REI Traverse 35 is fantastic and you CAN get water bottles out easily. Maybe she might enjoy an REI pack as well. Also going to REI for a proper fit is a wonderful experience. Last time I went to look at packs I ended up dancing with the sales associate. We had fun!
(Testing for the pack to be well fitted and stable on my body.)