Thanks for posting your questions - we're Aussie based & also planning an Alaskan cruise with HAL, but for 2024 and have been tossing up between a b2b, or the 14 day explorer; this has been really helpful!
We were on Ovation a couple of weeks ago; our boarding time was 2pm - we had lunch nearby, and by 1pm the line to check in was much shorter & they opened it up to all remaining time slots, so like us you may be on board earlier than you expect.
We cruised on Norwegian Jewel back in 2018, had the drink package deal + 3 restaurants as part of the price, gratuities on drinks weren't included ; i would check the fine print of the current offer for clarity.