Here’s what I imagine the technical sketch for Hillary’s jacket looks like.
It’s a bit like diagnosing a patient you’ve never seen in real life, but here are some possible approaches to fixing the problems we can see in the photos.
The armscye looks like it needs to be raised so the base of the armhole is not so low. Higher armholes can increase the movement range in a jacket sleeve, if there is enough ease in the sleeve as well as the body of the garment. One of my pet peeves in RTW is the plague of low armholes in larger sizes. Just because a person has more girth does not mean that the armhole has to get closer to the waist….in fact that has the opposite effect of causing the sleeve to tug and bar across the arm, as well as distort the side of the jacket when the arm is not at rest by the side of the body.
It’s hard to say whether Hillary is truly a petite fit in the upper torso, but certainly for this garment we could take some length out of the armscye. So let’s raise the armhole up a bit.
We could use some more length in the front as well, as the hem is hiking. It’s possible that an actual full bust adjustment is in order. Some length could be added and a small dart eased in at the side bust along that vertical dart that goes into the pocket.
The high hip and low hip (at 4” and 8” from the waist, respectively) could use a bit more ease. I would distribute that on all of the vertical seams, as well as adding a wee bit at the center back seam.
The sleeves are a bit more problematic, as we don’t want to add to length in the armscye, but we do need more girth at the bicep. I would fold out some length in the cap to account for the raising of the armhole.
This drawing shows how you might add to girth with a bit of slashing and spreading without adding to the circumference. You might have a bit of additional work easing in your elbow dart, but that can be managed.