Yes, you should be able to make it a one piece dress. You would be skipping the waistband and just be attaching the bodice to the skirt waistline. (because of the corset I can tell if the top extends past the top of the skirt…if so, you may want to shorten the bodice a little bit.) As far as the princess seams for the bodice, you can really put seams where ever you want. Place the paper front bodice over the front of your body and draw a line directly where you want the seam to be. (maybe get a friend to help you.) Then cut the pattern on this line. Wherever you cut the pattern, tape on some paper to add seam allowance and then you can cut your fabric pieces. Hope that helps! good luck! 🙂