NCL stands out for me. We have been on 20 cruises over 5 each on Carnival, Celebrity/Rccl/ and NCL. One on Holland, Princess, and Disney. Never had a problem on any cruise from the staff. NCL staff's seems to be under less stress and not to busy and overworked to visit. NCL always very gay friendly and we meet more gay travelers on NCL. Love free style dining and so many choice of when and were to eat and we don't have to bring our tux or even a suit.
We live near Galveston and do avoid Carnival not because of the staff but because the Passengers tend to be not very gay friendly, we seen to always be assigned table mates uncomfortable with us. But only out of Galveston, have done Carnival out of other ports and no problems. And you can always dine elsewhere or have the assignments changed.
NCL Gay friendliest, affordable, great entertainment, dining options.
Celebrity Our second favorite for the great service and spa's
Carnival Great for a party, younger crowds, lots of good food.
Thanks for reading my two cents. Clay and Stephen