Champagne is for everyone, one of the new "enhancements". White glove service and being escorted to one's room is for everyone, doesn't matter the cabin level. If you embark early you will not be escorted to your cabin.
I'm kind of alarmed at how many people are concerned about the age of the Century. I could see a ship built in the early 80s and earlier, but any ship built in the 90s simply isn't old. And maintenance is a line issue. Celebrity, HAL and Princess tend to keep their ships in better shape than at least NCL and RCI does. Yes, there's wear with use, but there is in any product. So, the unprecedented and rather unnecessary shipbuilding boom has caused passengers to think that they should be concerned with 4-10 year old ships where once these ships were considered relatively new.
Think about this, if you were going to New York City and staying in a hotel would you go for the newest hotels or for the highest rated ones (if they were affordable). Would you not stay in the Plaza or Waldorf because of their age?