There is a very interesting discussion going on in some of the cruise blogs I frequent when I'm looking to book or have already booked a cruise. The one I'm talking about deals with what you're willing to pay for to be included in your cruise price. If you've cruised before, you know what I'm talking about. The prices for cruising have almost stayed the same as they were 20+ years ago, albeit the category of cabin you can get for the money. 20+ years ago you weren't going to find balcony cabins at any price. And what has changed for most lines except for one is that there is no longer a class system, what I'm saying is that everyone is going to eat the same food in the same dining rooms, use the same pools, and entertainment venues, etc except in the case of Cunard (which is linked above in "one").
My take......I've been in almost all categories of cabins from the tiny inside that we tried our best to only sleep and shower in, to the slightly but not much bigger outside with a small port hole to the more luxurious suites which I have to say I prefer at this stage in my life. When we were paying for 4 the really nice digs were out of the question.
Now at this stage we like our cabin and verandah, we like to sit and watch the world, listen to the sounds of quiet and see it all without other people around. I try my best to cruise at least 2x a year, sometimes I'm lucky enough to get 3 if I shop hard enough. Although I like my own verandah, I would definitely take an outside on Holland America's R or S Class ships - they have a good sized cabin, and bathroom and if you are fortunate enough to get a C category outside you will have direct access to a public verandah that is tops in the industry. The cabin itself needs to be close to 200 sq ft or it's not for me.