DOL butterfly rain jacket

I purchased this Daughters of the Liberation rain jacket on Poshmark a few years back and find that it just got in a bit snug in the shoulders for me with my new workout routine and would like to re-posh it. There are imperfections that are shown in the pictures, so please view those. There is some general wear and tear along the edges, but as I have not washed it, it's possible that those may easily come out in a hardly noticeable.