Glad to hear HAL is taking good care of you. We were so impressed by HAL on our Baltic cruise last year we decided then and there to try them on our next Hawaii cruise; and that was even before we knew Princess was cutting down to 14 days.
We went in April and it was cool the first two days out and the last two back. We thought the Lotus (covered) pool on Island Princess was just fine, but not many were there--which was also fine. This is definitely the cruise for those of us that like sea days.
It is also the cruise for those of us that live in the West and are sick of being treated like baggage on airlines. On our recent four and a half-hour flight to Ft. Lauderdale the ONLY food available was a snack box for $5. So it is no wonder any cruise round trip from the West Coast fills up early.
And to your question about which side: it dosen't really matter because most of the Island hopping is done at night. If you cruise from Hilo to Kona it might be nice to be on the starboard side to see the volcano; or on the port side if you go from Kona to Hilo. But the wind was so strong we couldn't use our balcony anyway. We got a better view from the Horizon Court.
Have a great trip. I know you will.