Assistance with checking alterations

[MANUMICHEL]

Hi there! Im new in both tailoring (Ive started studying for like 3 months now) and in this thread, and I've been particularly interested in fitting and alterations, since I believe its highly important (It really makes bespoke actually "Bespoke") and its something that I can exercise without necessarily having a client and that jacket, although its highly recommended that I do, and I have been doing some alterations on my own jackets.
Anyways, I did two "Virtual Fittings" if you will, with images that people sent not so long ago in another forum, and I detailed the causes and fixes of the problems which I could detail. Basically I need help actually "Correcting" these fittings If needed, so that I can also learn everything there Is to learn! Ill attach the images down below.

[Hendrick]

I am having a hard time believing that the first and second sleeve are the same. Nevertheless, draw a line between the two back armpoints and see where the "grimasses"come from. First, your back center seam, from this line up needs more curvature; the body needs it because it is pushing up and pulling width. Note that more curvature ads length so the excess length from the line between back arm points and back collar point will only get worse. Correct the length. Your back waist needs adjustment, but specifically not only from the center back; the back parts will need more curve. The sleeve position is not correct; the sleeve "blows"below the upper arm. The left shoulder is lower; clean it out and correct the sleeve accordingly.

Cheers, Hendrick