Wow, it's gorgeous! Very retro. How on earth did you come up with the pattern?
I was going off inspiration from two dresses:

So it took careful observation of those, taking every single possible measurement of myself and dividing that into how many pieces I wanted with seam allowance around everything.... bit of fudging and adjustment and somehow it worked. As for the bustline, I kinda tried to trace this top I have which was hard because it's three pieces. Tried to hem it which was impossibly hard because it's curvy, forgot seam allowance on the back piece....etc. So after the hemming looked like crap I added black hem tape and it gave the desired effect.