Imo it's a comfort zone/playstyle thing. I personally will hit +9stam bonuses that require 1 red hybrid gem with a +10exp/+15stam gem if I feel like my expertise is too low for comfort. I personally would get edgy about dropping that low, but other people won't care. Just taking a quick glance at her armory I'd say her best option is to go for the Cataclysmic Chestguard next with her emblems of frost. It'll solve quite a few problems, then probably go for gauntlets of the kraken after that. Also, never gem 10str/15stam as a warrior. Str is not as good of a threat stat as expertise until hardcap (57 expertise, which no ICC warrior is in danger of hitting) but neither stat is as good as having a proper spec and rotation.
Also, there is 40 expertise/40 stam food that you can use if you feel that you're too far below the cap.