Boob envy aside (and there is that), I think #2 was overall the best shot. It's very complimentary to her, pretty sexy, a really nice pose and just overall pretty cool. The one thing is it feels a little tight on the lower and right sides and too open on the upper and left. I think a bit of cropping would help, but it's unfortunate that you (probably) don't have a wider image to give her a bit more room on the other side.
The shot where she is in the bikini and dead-on doesn't seem complimentary to her body shape- I think having her angled a bit works more. The shot where she is leaning back seems like her pose is a little awkward/uncomfortable, and the brick and such seem confusing to me compositionally.
In all cases I think you want to be sure that the pose brings out the best in the model. In her case, go with those curves and accentuate them and look to avoid the flat/straight looks.
Note: I'm not a big people photographer, so take these as reactions from a generally experienced with photography and an observer of portraiture.