Yes, it's easy to think you have all the space in the world to get all the engineering packed into a ship, but in reality it's very intricate. Also, the logistics required to make a cruise go around is quite amazing. I really enjoy cruising as a form of holiday, it's a very relaxing way of seeing multiple places, and there's so much to choose from with regards to activities.I've sailed on the Mariner of the Seas and the Freedom of the Seas and I've got to say that both times I was very impressed with the design of both ships. So much so, that for a while I even considered going into school for marine architecture (this was when I was 16 and 18 respectively, before I went to college). To this day I sometimes fantasize what it would be like to work as an engineer in the early design stages of those ships, though I'm really happy working on performance cars instead.
The Titanic was built to be the Concorde of it's day. It was primarily a means of transportation and the luxury of it was the speed at which you could cross the ocean. The dining rooms, grand staircase, pool, and other amenities were there to help justify the cost for first class passengers. Crossings were generally either boring or horrible, depending on the weather. The Queen Mary II is a modern liner, but they realize that they have to offer something other than a crossing to get people interested. Remember that the Titanic was the height of modern amenities at the time, so to keep with that style, a modern liner needs to offer today's modern amenities. That doesn't necessarily mean water slides and climbing walls, but it does mean some form of entertainment; otherwise is it just a glorified ferry.
otherwise is it just a glorified ferry.
Not disagreeing with you in any way but with the mystique surrounding the Olympic class liners, Titanic in particular, I am sure there is a business case to build one and have her ply her way between Southampton and New York. Sure half the people on there would be nouveau riche Chinese middle-class tourists and the tickets wouldn't be cheap.