gah! lost my post
I looked at your pictures. I wouldn't call you apple shaped so much as just square.
Many people do not realize that the skin beneath the breasts is just as thin and fragile as the breast itself, that's why you bruised in the too-thin-fabriced corset. This go 'round with better fabrics should prevent that. I have stuffed single cotton balls into the channels of commercially made corsets to pad them without ruining the outer appearance.
A well fitted, well made corset should not allow you to slouch. Both in the fabrics chosen and the construction method.
Where the corset sits on your shape makes a difference. It's top and bottom edges can be placed to make you look twenty pounds lighter or twenty pounds heavier depending on where they sit.
In your case, I think
what you want (please correct me if I am reading this wrong) is to create a waist visually. Easy! Do not make the corset a shape different from yours, shape it to you
. Don't stop the bottom edge at your natural waist or at your bending zone, these factors will create a heavy look. You want to carry that lower line down toward your hips to create an illusion of flare (A pear shape wants their ending line to be halfway between their narrowest point and their widest point on the hip line. A perfect hourglass shape wants that line at their narrowest point). You can angle your seams in toward the center, even just put surface decoration on, and create a tiny waist without torturing yourself.
Look at this dress: https://scontent-a-iad.xx.fbcdn.net/...68969675_n.jpg
See how the detail lines on the front make the waist look tiny? but there is NO WAIST to this dress! It hangs from the shoulders barely hugging the form, it's almost straight up and down! You can do that (okay maybe not with ten pounds of glass beads, but you get the idea).