We've been on the Solstice, she's a really pretty ship. They have a bochi (sp?) ball area with real grass, a glass blowing show, and a beautiful dining area. The rooms did have a sofa in the balcony room. The bathroom was not laid out any different than a normal bathroom. The Epic is the only ship that I'm aware of that has the toilet on one side and the shower on the other. We sailed her last year and it isn't that bad of a set up. There is a curtain separating it from the rest of the cabin, and there are enclosures for both the toilet and the shower. I actually liked the concept as I could brush my teeth or take a shower while my hubby was on the toilet.
We've sailed the Emerald Princess which is a sister ship to the Ruby. She's beautiful, they have the Sanctuary which is adults only, the International Cafe, Specialty Restaurants although the food in the main dining room is wonderful, Anytime dining or regular seating, however, there was not a sofa in the balcony rooms.
The N.Amsterdam is HALs newest ship and we've not sailed on her or the Eurodam. There are some great reviews from the Eurodam, but I've not read one from the N.Amsterdam. I'm sure their ships are beautiful, too.