Black dress makeover begins

I got this commission from my boss at the Old Manse, after I made her that brown silk dress. She had an old black silk dress and an inkling that it wasn't quite right, and asked me to make it over into an 1820s dress, perhaps one that could be used for teaching purposes. Which of course I decided must mean "let's make it all by hand!" because I'm a nerd. But before I took the old dress to pieces to make it over, I took loads of pictures because I thought it might be interesting to see what changed and such.
The original dress looked more or less like this.

My mannequin does it no favors, being entirely too small in pretty much every possible way, but even on a larger figure, its clear that the weight of the fabric would still result in a limp-wrinkle kind of look.
The sleeves are this sort of medium gigot shape. They're held up on the inside with little sort of fans of pleated fabric stuck into the armsceye.

The period this dress supposedly aims for is mid-1820s, but although the gigot sleeve did come in around 1825 I still think it winds up looking a bit too fashion-forward. (Context: The dress was supposed to be worn by a minister's wife who was quite old.) The depth of the waist and the distribution of the gathers also felt very 1830ish to me.
The center front had this large decorative buckle, which was really much too heavy for the bit of fabric holding it up. The actual design of the buckle seems passable to me, although the one missing rhinestone is a bit sad. It's worth noting that this dress saw maybe 5 or so years of occasional wear before I got at it.
The center back buttoned up with large buttons. Like very large. Very plastic, with enormous machine button holes, and this sort of awkward placket situation. I'm not really sure how this closure came about, especially since there are so many way easier period closures.

Apropos well-worn dress, there were a few signs of wear in the garment, kind of amusing ones?
The neck facing was just a little narrow bit of cloth, cut on the straight if I'm not mistaken, which liked to stick up at all angles.
And under the arms were these weird stains... In the picture it looks white, but it was actually sort of glittery. I don't know if that was well-ripened deodorant stains, failed dry cleaning, or some kind of like febreze. They didn't show when the dress was worn but they were a bit unsettling.

 So anyway, I took the whole dress to pieces, mostly by cutting along the stitch lines. The original stitcher had faithfully zigged along all the raw edges, which was good thinking on their part but of course made unpicking things a bit more difficult than I'd hoped for. Then I started making up my new pattern. I did it by the pillowcase method, where I make a fabric pillowcase to approximately the measure of a torso, cut little arm and neck holes, and then put it on a person or form and shape it from there. Since there is no planned wearer for this garment, I just sort of picked a size at random. I figured 5'6"-ish and proportionally a bit wider than me should cover a fair portion of the volunteer pool most likely to wind up in this dress. Plus it's going to have a drawstring back so there'll be room for variation.
For the design of the dress I'm taking my inspiration mostly from this dress from a Norwegian museum. There are great pictures, from front AND back! It's the exact right year, and it's relatively simple so the style lines are easy to read. The look I'm going for is basically, simple silk day dress for a conservative New England lady who is also trying to be a bit up on the fashion. I'm going to do roleaux trim on the hem instead of ruffles, and probably a simple puff on the sleeve, and I'm putting in a waistband which will be magically adjustable at the back

Right now my progress consists mostly of a page of nearly unreadable notes and the lining pieces cut out for the bodice. To fix the whole limp-wrinkle thing I'm flatlining the whole dress with this beige quilting poly-cotton. It's a "historical color", so Members of the Public turning it over won't be confused and startled, and I figure the poly content will only be obvious to other textile folks, who represent a fairly small percentage of MoPs.

Next: baste the bodice lining pieces to the black silk outerlayer, figure out what's happening with the sleeve and the skirt, and sew the thing together. Also, make 1000000 piping, and that roleaux.