I would absolutely suggest avoiding Dec/Jan...Most likely, the weather will be against you. The wind will be too strong and you won't be able to properly enjoy Amanoi's fantastic exterior space. Will likely be difficult to swim off the beach in Dec/Jan. Doable but not fun. Speaking from having had clients visit in both Dec and Jan (didn't have flexibility) with weather being an issue. GM Nicholas and Joy also would suggest the same to guests.
However, if you can push it till another time, I'd highly suggest it as this is one of my favorite Amans! The new Amanoi Pool Villas are stunning and great for families as well.

Rosewood looks interesting and may have some intro offers to public or Elite Advisors.