Hi there! So I'm done with the pattern, and the mock isn't too bad. I had the not so good idea to use plastic boning on the lacing strips for the mock-up, because steel boning is in limited quantity here and I didn't want to cut out a random lenght and then have to cut it again, and end up waisting a few inches of it. Well anyway, the plastic ones ended up bending in a lot of different ways, making it hard to figure out if the problem was the cut or just the boning.
Pattern, with the seam allowances
Back of the mock-up. As you can see the top is weird and bending, and I think it is both because I still have to take it in a little and because of the cheap plastic boning. it should look much better with the steel boning. I also might have made the waist a little bit too small compared to the rest, so I'll probably add half an inch to the pattern at the waist.
Front of mock-up. I think it looks fine from the front. It's just the back that's weird looking. I'm sure I will be able to work it out.
Oh and I also found this nice fabris in this small fabric shop close to my house. It would look good as a corset, or as a period garment. I still don't know what I will use it for. If I don't find anything else I'll use it for my 1911 corset, but I can't help seeing some 18th century stays in it. And the fabric is so pretty maybe I should save it for something that will not be hidden under a dress...