I’ve also been on Norwegian (Sun & Spirit). I’ve been lucky with my cruises. Ships clean & well cared for, good staff who make every effort to be helpful. We usually travel in ‘off’ times, with fewer people on board. Maybe that helps. In fact, our first trip on Splendor was cross-Atlantic in November. There were only 30 kids on board. Lots of old folks though. :-)
I’ve been on 7 cruises in 7 years, 5 of them have been Norwegian. The first two were on Royal Caribbean, but after one sailing on NCL I knew I’d never cruise anyone else. We’ve never had a bad cruise with them. I’m always planning my next one!
On topic, Costa is having a run of really bad luck. Glad I’m not on the ship.