Explora currently at 500 passengers +/-50. Pretty consistent count for four weeks. We do early dinners, so not a good judge of restaurant crowding. Besides food, the crew is top notch at management level. Overall feel that ship not crowded at 500. But to answer your question about issues of a fuller ship. Personally, I do not want to be around so many humans. 500 seems tolerable, but not nearly close to perfect as 200.