I took a week off, so that's a late response, sorry.
- The dump site at Gilgo Beach is more of a drive-by dump site. That means, the victims as individuals don't have meaning. Look for comparison at the Green River dump sites, or, still a classic, Ted Bundy's Mt. Taylor dump site. Those are real re visitable dump sites. Gilgo Beach is not. Too mear to the road, to near to Oak Beach and too much poison ivy around for committing comfortably necrophilia.
But the specific nature of the Gilgo Beach dump site is that of a trophy collection. Means, the killer jogged his memory by driving by, maybe slowly, maybe at night. Which indicates, at least to me, what he savored there was not sexual memories (those are based on individual victims) but a generalized sense of victory. The single victims means nothing, the sum of them symbolize something for him. Another one of the hints, that he is at least partially mission-driven.
The other misconception is, SKs don't stop if they are not count. Psychopaths don't. They are rage fueled. Sociopaths can stop, and they will if they find something more exciting for themselves, or if killing and playing with the police gets boring. BTK for example stopped when he founded a family. And for sure, there is a reason why Zodiac stopped and I bet, it wasn't because he got arrested for an unrelated crime.
But yes, I agree, especially SCPD should look for other dump sites which were created after the searches of 2011. The last body in the Gilgo Beach dump site was from 2010. So, if nothing has stopped LISK, where are the 2011 bodies, or most likely in the meantime, at least one 2012 body? Now, we know, LISK can be pretty bold. So at least, SCPD should check regularly the vicinity of the Gilgo Beach dump site. Because the killer may have the idea "they searched there already, they think, it's clean, so they won't come back"