If you book a lagoonview room, you will have a view of the MK. A few rooms are partially blocked by bushes or trees but I think it is very few.
Wishes is wonderful from the Polynesian but be sure to try to catch it in the park if you've not yet done that. There are some effects that really can only be seen within the park.
Try to see the Electrical Water Pageant. It starts in front of the Polynesian every night at nine.
Have a magical stay!