Lucky you, Amanwana is my favourite aman. (Jiwo is a close 2nd)

The lower the number of the tent, the nearer it is to the lounge/restaurant.
This is not a real problem as it is a tranquil resort and there are only 20 tents.
Personally I would take any tent ocean or jungle as there is very little difference.
On one of my visits to amanwana the late princess of wales and her friends stayed at tents 19 and 20 which are the furthest from the communal area. If maximum privacy is for you, a tent in that area might be best.

I have not stayed at Bulgari so cant help there.
Enjoy Indonesia, im sure you will have a wonderful time.