A few months ago, when I was having some issues with my flash trigger, I decided to go into the room that was traditionally my office area and use the the window for portraits. I started by taking pics with the model right beside the window, but as time has gone by, I now stand on the other side of the office (window beside me) and take pictures with the model not directly in the window light. It's definitely been giving me some nice results. I just put a little diffusion over the window, of sometimes nothing if the day is overcast. It also allows me to shoot at shallow depth of field, usually around 2.8.
These look great! Well done!