From my limited experience with the Fixed Wing navy (read- no traps- yet, but have flown the ball) versus the small-boy single spot at night world (HSL) the things that will fvck your world in the helo in a non-emergency environment are:
1- The descending, decelerating approach. You normally have the crewman calling closure, but that is not always spot on. Easy to get sucked into the black hole. I have had vertigo at night behind the boat, and its not pretty.
2-Coming in too hot due to not judging closure. Hard to do at night. Come in too hot, risk smacking the superstructure. Come in too slow, risk backing down or the black hole. Keep in mind, on a normal landing, you are ~15 feet from hitting the superstructure. (someone correct me if I am wrong)
Neither of these take into account really bad seas, stupid SWO tricks, or EPs.
Both are much safer with 2 pilots. As much as I wanted to be rid of being an ATO (think NFO), looking at it from a distance, I think two pilots is a good thing.