We've stayed in Tahita twice. I wouldnt want any other building. The view is great and close to TTC. We always walked there to catch the monorail or the boat launch, its closer than the GCH, and its not a bad hike to the bus stop. I would try for the 2nd or 3rd floor though. We had 2nd floor both times, what a view, you'll love it. Id be going back again this year but DW wants to try the Beach Club, she wins
In all seriousness. I've never stayed in a garden view, but I would check the map of the resort and find a building between the GCH, TTC, and the Valcano Pool.
There are all sorts of variables with garden view rooms to consider, and I think that the specific building you would prefer will likely depend on what's most important to you. To determine that, your best bet will be to go to Steve, the Tikiman's website devoted to the Polynesian. He gives descriptions of each longhouse plus the pros and cons of each longhouse. I used his site to determine where I would like to stay the most.
His site is blocked from these boards, so I cannot give you the link, but I will tell you to Google "Tikiman" and "Polynesian." His site should be the first one that comes up. Happy planning!