I think the only thing that could be tweaked would be your shoulders because it seems like the teddy is a bit big for your shoulders. However, it is almost impossible to have the perfect fit since this stuff isn't bespoke. If you size down you risk having more cropped sleeves and a more cropped body which really only looks good for thinner physiques. If it is easy to try on a smaller size then I would check it out just to have that information to help you finalize the decision.
I think some of that is due to holding the camera and trying to get a decent shot. It actually feels pretty good in the shoulders otherwise.
I think losing any length in the body is going to look awkward on me, certainly when closed, since then the jacket will sit just above the waistband of my jeans.
I wish I had a Saint Laurent store nearby, but I mostly have to make do with researching stuff then ordering online.