Wejust went on the Grand and had B433 and we were ok with it. The situation is like this - the cabins UNDER us - had BIG balconies - but we looked right down onto it - the cabins ABOVE us were even with the end of ours, so, we did not get the passebgers looking down at us - we could also see the balcony on Dolphin deck as well.
So, do you want to look at others? Do you want to look at them? either way we had fun and enjoyed it. One consideration - we took B433 because it was VERY close to the center elevators - My Mother -in- law was with us, and that was important - My wife and I wanted the stairs (gotta work off those calories) - MUCH to our surprise - NO STAIRS . . . at our deck level. this created a lot of walking to one end or the other to use the stairs - we did it, but we did use the elevators more than usual this cruise - due to the lack of stairs and the ship being ssssoooooo long -
I would do it again, but would get a cabin closer to one of the ends, waiting for elevators was amazingly long. Lots of elevators, but lots of passengers too.
I was just on the Grand Cabin D728. It's true, the balconies from above looked down into ours. It didn't bother me. Our cabin was aft and I really liked that. Aft tend to be a smoother ride than at the front. Have Fun.
I find the balconies on Caribe (1/2 covered) and Dolphin (fully open) to the rear are the best. Baja and Aloha have small, usually covered balconies. All of the Grand Class ships are wonderful. Have Fun!!!