Thanks everyone! (Sorry for posting in the wrong forum. For some reason it never occurred to me to check the Destination subforums). But now I know (now, the question is: will I remember this information? haha)
Yeah, I suppose we could certainly have the Hotel (we're staying at the Embassy Suites Waikiki) hold our stuff and maybe just continue to sit by the pool and relax.
I think we'll go that route, and then if we have like 1.5 hours to kill at the airport, use the free tickets (our next travel won't be until Jan 2019 as I'll have spent my budget on 3 weeks in Hawaii).