I have always been one who hated the "last night envelope stuffing" ritual. I was happy when the cruise lines started to automatically add the gratuity, service charge or whatever you want to call it, to the onboard account. It made life simpler. If I want to give someone extra then I do it. If I or someone wants to give a note of thanks to someone they can still do that.
I personally would like to see the gratuities eliminated and just rolled into the cruise fare. The problem with that is that you would no longer see the "$350/seven day, inside cabin" deals that lure many people in. It would end the International issue where non-Americans feel they are being taken advantage of by having gratuities automatically added to their account or "expected" to give the suggested amount.
The trend that bugs the heck out of me is that since the cruise lines have implemented the automatic gratuities people now think they have to give MORE otherwise they are a cheapskate. If someone wants to give a crew member extra that is their business but it is not required, suggested or a cruise line policy. You are not a cheapskate nor will you receive worse service if you don't give extra. If you do receive bad service then bring it to the attention of the Head Housekeeper or Guest Services ASAP. If you get the "sob story" from a waiter or cabin steward about how hard they work and that they don't get their fair share of the gratuity pool don't let that sway you. These are the crew that "usually" are the least deserving and you can feel sorry for them but you are getting suckered. They may get less but there is a reason for it.
I have tipped extra many times but I don't do it for someone doing their job. If my cabin is straightened twice a day and I get clean towels and enough toilet paper then the person did their job and I feel no additional gratuity is required. If I ask for additional ice each day, a different lounge chair on the balcony and additional clean up of the room, then I will probably give additional.
My own personal opinion, with no scientific basis, is that most people who pre-tip "Slip the cabin steward $100 at the start of the cruise to ensure good service." do it more to make them look and feel good rather than to get good service. There is no guarantee that you will receive good service if you pre-tip.
Gratuities have always been a "hot topic" and until they are eliminated it always will be. Sort of like smoking.