We recently got back w 12 and 10 yo girls, and 7 yo son.
During checkout an overly friendly CM, seeing the account and talking about future visits, was spontaneously commenting about the programs for kids and lamented that she wished Aulani had as robust a tween program as it does a teen program. Unsolicited she told me that she suggested bumping up a child's age to qualify them for teen programs if you think your child is emotionally ready. They are on an "honor system" she said and do not check ages further than the reservation. She went on to say that she used to do it in the computer for guests all the time after check in if they could benefit from it... but then was told to stop.
I'm not sure my 12 yo would've felt comfortable with the teens, but the tip is worth mentioning.
Aulani needs more tween-specific activities. They had a few at Aunty's: tween crafts, for example. They need more. They could even be the same standard Aunty's activities but aimed at 9-12 yr olds. So much of the issue for tweens, mine at least, is the emotional barrier of being in the same room as 4 yr olds.
Having said all that, they all loved the comedy night and the tween craft night.