Since I have never been in a suite, I can only compare between the following ships: Fantasy, Sea Princess, Grand Princess, Rembrandt and Millennium. Space wise I would have to say the Millie wins. For water pressure, the Sea and Grand would win. The Rembrandt actually had the biggest bathroom, but let's just say it was OLD and let's leave it at that.
Have never been in a suite, so all I can compare is the regular rooms. Between the Mercury, Rhapsody of the Seas, Grand and Golden Princess, and Sun Princess the Mercury wins hands down. The shower was quite large. The bathroom as a whole was quite a bit bigger than the other ships also.
Disney Magic's bathrooms were the best. They were split in two - sink/toilet room and shower/tub/sink room. Very convenient for multiple people! Millie's had lots of storage space, but Disney wins this one.
I'm pretty sure it was the Nordic Empress...
The bathroom was fairly spacious. But, the big point was the shower. It was circular, and had a clear, plexiglass, semi-circular door. It was a lot roomier than the standard square shower.
The Radiance - Cat D cabin bathroom wasn't bad except the shower was very small. It also didn't have a lot of pressure. After I took my first shower I came out and told my husband it was like taking a shower with a waterpik. It was a great cabin but a bigger shower would have been nice!
So far the suite we had on the new Carnival Spirit wins hands down for me-- even if the jets were not working- very huge to say the least- double sinks- oversized jazzuiz bathtub- marble and lots more-- even the toilet didnt make the usual loud flushing sound.
Reading Kathy's remark about showering with a Waterpik reminded me of the very low pressure in our last suite's shower. Have you ever noticed that if the water comes out of the shower head slowly, that you shower slowly? It seems like it took forever for me to get the shampoo out of my hair!! It seemed like I was moving in slow motion!
I think it's like music when you're driving. If I listen to upbeat music, I drive faster. (FYI - This excuse does NOT work with the Highway Patrol.) :^)