We switched to mainly sailing RCL years ago, we like to do B2B and the cost savings is shocking. I will disagree with your pricing comment. I book the sailings we want the day we decide what weeks we will cruise and then sit back and wait. I always save something off the price but it's more often than not that I can save a thousand on each sailing, before paid in full. It's a simple reprice on the paperwork. I've never received a better price after PIF.
I have heard from some that if there is a discount on your cruise after PIF you can only get it back in the form of an onboard credit. Since I have never experienced it myself I would not put hand to Bible but while speaking with people on our cruises, this is what we have been told.
As for the drink packages, I don't think they are priced badly. As with you, we don't spend a lot on alcohol on
DCL, I don't like to get a surprise bill at the end of our sailings. Having said that, I always purchase a drink package on RCL. It can always be repriced as well if the cost goes down. I think the most I have paid is $72 Canadian a day which, while it sounds like a lot, includes not only alcohol but also non-alcohol frozen drinks, smoothies at the gym health bar, milkshakes at Johnny Rockets, water (both sparkling and still), canned soda, fountain soda (both canned and fountain are covered at the bars, they are not on DCL), specialty coffees and, last but not least, wines. DH doesn't drink at all so he gets the drink plan that includes it all except alcohol and I've never paid more than $25 a day for that, often less. We average about $100 a day on a drink package between the two of us and with what it includes, it's a bargain.
What we like to do is pick up cans of soda, bottles of water (both types) and keep some in the cooler in our cabin so they are always there. We sailed DCL in Feb and a case of water cost us $55 plus gratuity, not my idea of a bargain.
Anyways, we are all different so I understand what you are saying. It may be your experience but not ours.