We travel with a service dog..she is going to be on her 6th cruise in September and 7th in November.....We've learned a lot and have some suggestions for you....
Don't be hesitant to do it.....it's wonderful! And truly has made our cruising so much more fun!!!!!! :p
We've cruised on Celebrity/NCL/Princess/Carnival and HAL.
The Best (most accomodating-all around) - HAL
The Best set-up (potty-box) - NCL/Princess
The Best crew for dog friendliness HAL/Princess
Passenger friendliness...every ship we've ever been on. We only 1 passenger in all of our cruises who absolutely refused to eat in the Buffet area, with a dog!
If you have any questions about the ship requirements/easy way to deal with "special needs" departments/cabins/dining area/potty box/food/exercise/hotel/excursions/airplanes, etc. Ask away......
I don't want to bore you with all the details...so, I'll let you lead the way! ;)