Hi, Alexandra!
I, too, am a lady and I have a fairly similar build (5'7", 130 lbs), and I did my research and decided on the ATA kit. From everything I read and all the questions I asked, it seemed like it would be the best fit and easiest kit for me, since this is my first as well (I'm likewise no stranger to sewing and costuming). I've placed my order and paid for it, and now I'm just waiting for it to arrive! I'm DYING.
BUT...since I haven't started on it yet I can't say for sure if I made the wisest choice. The cost was right, the sizing right, and difficulty level appeared right. I'll let you know how it goes once I begin.
If you don't mind, I'd like to stay in touch and compare build experiences!
Alternatively, you could make your own using clear contact paper. It's a lightly adhesive thin plastic-like material with paper backing, and costs approximately $5.00-$10.00 for a gigantic roll at WalMart or any similar store in the kitchen section (it's used for lining cupboards/shelves). It's easy to cut, easy to peel off and does not leave any kind of residue. I use it all the time for my stenciling projects and it works fantastically.