Thanks for the replies guys!

I don't think the wife and daughter are *A members. The husband is SQ *A Silver (I think). Which program is better for them to join? I worked it out and I think the daughter would get to *A Silver if she joined ROP (TG requires only 10k or 15k in points) but she'd miss if she went KrisFlyer. The wife would miss just miss Gold on both (I think she'd get around 44k with bonuses). However, does SQ work on a calendar year? I know Thai is a revolving 12-month block from date of first flight.

The family is NOT fans of NZ so I'm not going to both suggesting AirPoints Dollars unless it would push wife to Gold somehow.

Which program should I recommend them to join?