I'm going to have to disagree with this, they have cut lots of perks. One I can think of off the top of my head is they no longer allow you to bring on liquor and limit wine to 2 bottles. They used to allow anything but that got cut. They used to allow you to drop items off at guest services for signatures, that is gone. There are definitely perks that have gone by the way over the years. They cut out the booklet they used to send out, its now just a piece of cardboard with a bit of information on it. They do still send out luggage tags....for now.
As for the late night buffet, are you meaning the pirate buffet? Not exactly extensive and very crowded. I have not seen any other late night buffets since they did away with the chocolate dessert party.....another perk they got rid of. Late night snacks are three or four hot buffet trays with a few finger foods and only in the bar district. I have found much better late night snacks on the RCCL cruises I have taken and much more in variety. They do still offer free room service though......again, for now.
We to enjoy DCL, in fact we will be on the Fantasy in a few weeks, however I don't see they are doing any better in the perks department. And your right, their prices are insane. We can cruise for two weeks on RCCL for what we pay for one on DCL. One of the reasons most of our cruises are now RCCL. You don't get a whole lot more for the cost with DCL IMO, but that's another thread.
ETA-I have never experienced a first run movie playing in our stateroom.