I studied the deck plans of the Grand Princess and the closest cabins to the bow are the Plaza deck cabins. They are on a lower deck. They will be noisy but more stable. The mini-suite cabins on the upper decks will have a bit more motion but they are not directly on the bow and will not have as "much" motion.
I do stand by my original statement that stern will have less motion but in my opinion, the location of the forward cabins, especially mini-suites, is not terrible for motion sickness. I would check with your doctor before sailing about motion sickness medication. I wouldn't let it ruin your cruise.
If you are close to the laundromat you aren't too far forward.