End of the day, everyone's cruise experience is different and you'll usually find those that review are the ones that had a negative experience over a positive one.
Me- I've cruised NCL 5 times on both big and small ships and never had a bad experience
Be mindful that Dawn is one of the smaller, older NCL ships so doesn't have all the 'bells and whistles' and entertainment that the newer, bigger ships do.
Also- the older ships do tend to have smaller cabins so another thing to take into consideration.
We've never had a bad cruise with NCL and enjoy the laid-back freestyle dining. If you're someone who enjoys formal dining and dressing up every night then this may not be a cruise line for you (though you still can if you want- it's freestyle).
I personally find the drink packages great even though I'm not really a drinker- no need to sign for every drink or worry about a large bill at the end.
Have most recently been on NCL Spirit and definitely notice fewer staff than before the restart, but this seems to be same across all cruise-lines from others I have spoken to.