I just discovered the first significant difference between HAL and Princess. When I booked shore excursions on Princess the charge was put on my onboard account but was not posted until the end of the cruise. I just found out that HAL posted the shore excursion charges the very day I reserved them. I've paid for them and I haven't even left yet.
Now you could say, so what? You paid for the cruise too, and you haven't gone yet. Should I pay for my photos, drinks and spa services up front? I don't think so.
So between this and the ease of navigating Princess' website compared to HAL, so far it's HAL - 0; Princess - 2.