Overall, the body attitude and posing fits the tone of the voice, which is great! Animation wise it feels a bit too spliney though. The transitions from pose to pose are too loose. Also, think of contrast, visually. How can you make this interesting without crazy poses and fast timing. Try to incorporate visual changes so that tone wise the shot doesn't feel stale.
For instance: what if the bench is more parallel towards us. She would still sit the same screen space (so off to the left, not in the middle of the shot). But she is looking screen left, head, eye and body wise, during the first section until "like... (pause)". Then she readjusts herself a bit like you have it, but turns the head to the right and the body a bit as well. So first she's looking to the left, lost in her own thoughts. Then, after the readjustment, she looks at the person she's talking to and probes him about the 80 or 90% and that's why she's making full eye and body contact, because it's more focused. You will have a visual contrast with the pose change and it will accentuate her focus. But keep the poses that you have with the shoulders up and head down.
Sound wise, make sure to include the little breathers in your animation, that's great material. For instance: the inhale around the x50 area and from x90 to around x120 (I wish quicktime could scrub through sound...). Those pauses are gold because you can incorporate your own little acting nuances without being too tied to the sound.
Hope that makes sense! :)