these are great. for headshots, typically tighter crops and non-distracting backgrounds are what captures the eyes of the "client" they're sending these into, so I would shy away from backlit backgrounds b/c it tends to take the attention off of the subject, this beautiful model.
You did a great job! for me, #1 and #4 are great headshots. The industry used to use mainly portrait oriented, but they're beginning to accept a lot of landscape oriented environmental portraits as well. the landscape portraits you have posted are great, I would just make them tighter cropped to show off that beautiful face.
great work!