Nice report. I love the South Pacific. I'll be going to American Samoa, (Ind.) Samoa, and Niue in November/December, and will have to stay in Tongata'pu for a night.
Did you by chance get off of the main island and venture up to the Ha'apai and Vava'u groups? Those island groups (part of the Kingdom still) are reputed to have the most beautiful beaches and clear calm water around.
Also, I was curious if you considered the 1 stop flight from LAX to TBU on ANZ (it leaves once per week and flies from LAX to Apia, Samoa (APW) then onwards to Tongata'pu (TBU) via 763) or did you go via Auckland to spend some time there and/or pick up more miles?.
I always love reading the (rare) South Pacific threads.