Well, I tried shrinking the sweater, and things went really well. I measured the garment first (thanks for this tip, Sheryl and karen13!). I used warm water with some Eucalan so that I wouldn't have to rinse. After I put the sweater in the water, I checked to see if there was any bleeding, and there was not, so I figured it would be safe with the higher temp.
I let the sweater sit in the warm water for 5 minutes, and then I squeezed most of the water out and rolled it up in a towel to remove the rest. I measured it, and it was still slightly large for my target, but since I didn't want to overdo it, I just let it air dry at that point.
After air drying, the sweater looked great. No uneven bleeding, and everything seemed to have shrunk evenly. The texture is still good. Next time I wash it, I will probably use cold water and see if the sweater will shrink that last little bit.
Thank you all for your advice! It was a life saver. Since I pretty much always have to wear petite-sized tops due to my short stature and narrow shoulders, I'm often missing out on interesting items. Being able to shrink stuff to fit helps expand the possibilities for creative dressing!