Niue or Raratonga. One side of Raratonga does face the parking lot and monorail . However my DS2 and I spent one night in a room there and the landscaping was beautiful. The parking lot was far away and not noticeable to me. The landscaping and monorail dominate the view.
We've stayed in the Tahiti building once before, but it was too far from the GCH for some members of our group who wanted to fill up their mugs early in the morning.
For mug refills and the like, to me only Rapa Nui and especially Tahiti are a bit of a hike. All the others are probably less than a two minute walk to Captain Cook's. Well, the far end of Tokelau might be three if you take your time.
We've stayed in Rapa Nui many times and I'd make the mug run in the am. Never bothered me. But the other longhouses are closer.
We stayed in Rarotonga. You walk out the door of GCH and it's only a few feet to the Rarotonga house. Very convenient with little kids. I would highly recommend it. Our room overlooked beautiful landscaping; I think the other side of the hall overlooked the monorail. Hope this helps.
That's my only 'beef' with Rarotonga. A 50% chance of a parking lot view is too high for me. But I will say, the landscaping makes it a pretty parking lot view.