Welcome to FT! Hope you enjoy your Hawaii vacation!
I'd suggest that you remove half the items off your agenda. Seems really ambitious and stressful to me.
DO NOT GO ON THE KALALAU TRAIL WITH YOUR BABY! (Sorry for the shout, but really need to get your attention on this. It is a really bad idea to have a baby on that trail (or any of the other ones you mention.) Really, your six-month old is best kept in the shade around the Grand Hyatt's pool while the parents relax a bit.
All the best in your decision-making and travels.