ive been on both royal and carnival and both of their pools are small and get crowded. carnival had two pools, one of which wasn't too crowded. royal only had 1 for everyone, and 1 for just adults. the slides on the carnival dont dump into a pool, just like a little flat part of the slide.
carnival might be your be ur best bet if thats what ur basing it on,
otherwise the kids seemed to have more to do on royal c.