Building 8-Boca Chica- lagoon views are great. I feel this building is the best. Also Building 7-Conch Key-, end of the building section(the T section) has views of MK. Building 9-Big Pine Key- has nice lagoon views of the Poly. I know there was a prior thread on this same topic not too long ago.
I used to love it when I'd work nights and was not too busy delivering things to room, and I could go up on Building 7's stairwell and watch some of the fireworks. I'd get to do this once in a great while.