1st - July, 1974 on the Homelines Oceanic cruise to Bahamas.
Last - Oct, 2012 on RCI Liberty OTS transatlantic cruise.
For us the best improvements are the size of the bathrooms. DW used to tell how she had to shave her legs w/legs hanging out the bathroom. Comedians used to joke (but was true); to take a shower just lather up the shower walls and spin yourself.
Another great improvement is balcony cabins.
Bottom line improvements to the cabins.
O F C'er