It's a gorgeous dress!
Lily Sawyer had some great advice. The easiest thing to do would be to make it to match your largest proportion and then take it in where it needs to be taken in. I have done that on occasion, when I'm in a raging hurry, but it's wasteful of material. Another thing I do when I have to 'fit' a pattern (and I do, often, because I and my girls are tall and long waisted) is to choose the pattern size that fits each part. For example, I think I remember you saying you're busty. The bodice is in three pieces, so cut the size that fits your top half. Then, if your lower half is a smaller size, cut those pieces accordingly. Lay the pieces out and make logical additions or deductions until the pieces go together. With a half inch seam, it isn't usually very hard to do so--that's a lot of fabric to work with! Making the dress out of cheap muslin (or some such) is great if you have the time and money to make it twice. I'm impatient, so I've only done that once
Finally, once you have your pieces the way you want them and you know they work, transfer them to a sturdier paper if you think you'll use the pattern more than a couple of times. Tissue paper is crap for saving/storing. You might have to put your new, tailored pattern in a larger ziplock baggie (with the instructions, picture, etc), but it's well worth the time and effort for something you really like.
I don't know how often you sew, but one extra thing I like is pattern weights as opposed to pins when you've laid out your pattern, particularly if the fabric is light. I've had pins pull light fabric just enough out of whack that the pieces don't line up exactly, and that's frustrating. Good luck!
