I have done exactly what you are trying to do ... I used a First Class Global Travel ticket to HNL (deviation at the end of a trip) and had the wife/kid use NWA miles, I joined them enroute in MSP (I jumpseated home at the end of the vacation with the family, sat between 2 large guys in coach). It worked out well for us. ..
Several Thoughts:
- NWA wouldn't upgrade my family for First Class, they said they considered it an international leg. They wouldn't let me (us) use the First Class Lounge, they said they considered it a domestic leg ... bad deal!*?
- We stayed at the Hale Koa, nice place, too bad that won't work out for you (we stumbled in to other FDX guys in the elevator). Even if you don't stay there, there is a "Travel Agency" in the lobby of the Hale Koa, I suspect you could call them and use their services even if you aren't a hotel guest? They have Island Bus Tours (including Pearl Harbor), bicycle tours (we did one, great fun) and info about staying on other Islands (maybe in other military facilities like the Hale Koa?). If you end up staying a reasonable distance from the Hale Koa, they have really good meal buffets and a nice outdoor bar by the pool. I recommend both.
- I have frequently used ID90's for family vacation domestic travel with good success but Hawaii loads are quite heavy some times of year, I didn't want to risk it.
- (Probably since 9/11?) There is now a military gate guard that checks ID's prior to driving up to the lobby of the Hale Koa. I couldn't help but notice that after the Army E-3 checked and returned my ID, he didn't salute me? I asked him about it and he replied, "I don't salute Naval officers because they don't show me any respect." I asked for his ID and his supervisor and called the base XO to express my bewilderment!*? I'll bet that problem has been fixed?
No doubt there's more gouge, I'll write more later if I can think of it.
Regards ... Mark