Thanks for the suggestions!
I added about 10" to the length (may take a bit off, as it feels just too long).
Then I sewed on a tapered inset neckline, just used a twin needle to sew it under the already finished neck edge. After that, I just cut two 6" wide strip of the teal at a random length, pressed it in half, tapered it into a semicircle, then sewed it under the armhole edge. I think I could have put them in a bit tighter though, as they poke out a bit much.
Does it need anything else? I have a small piece (about 12" x 30") of the teal left.