Tahiti bldg. was great for our family!
It is a little bit of a hike to pool and GCH, but the access to TTC with kids can't be beat, IMHO! Easy monorail ride to MK and Epcot AND busses to everywhere on property. We sometimes jumped on board the big ferry to MK.
Another plus for Tahiti is the beach. Down at that end it was quiet and relaxing, almost our own private beach. We often walked out to catch the EWP, as we were on the 1st floor.
I am not sure when you are going, but our last stay was in December. With early park closings we'd go to the pool at night. Between the swimming and the little stroll back to the Tahiti longhouse, our kids just passed out.
FYI, Tahiti is currently the temporary locations for concierge guests but I believe that will be finished by early October.