1. Not to me- I use my NW miles whenever I can.
2. Stby, not confirmed seat when I used them years ago.
2b. Yes. CBA chap.1.B.2. Try using the Word version of the contract and just doing a word search (such as "international") whenever you are looking for answers like this.
3. CBA Chap.8.C.3.d.ii.2.(a). Can expense up to 3 nights at hotel in lieu of scheduled D/H ticket. You can also ask your ACP for more nights if the ticket expense allows it (good luck with that one in today's climate). Or, you can expense one night without sacrificing your ticket.
4. There are several Army and Navy bases with beach cottages. Check online for those.
5. I checked with Crew Travel Audit and have been told twice by two different people it is 3 CALENDAR days, not 72 hours.
6. Check with the military MWR's for deals on rental equipment, etc. around the Hawaiian Islands. Have fun.