Sounds like you have some good queue line material working, but I'm still not getting the premise or theme. Disgruntled workers and kids with parent issues don't really have a lot of pop. I'm not sure what the danger is there, unless you are talking about postal workers or the Menendez brothers.
And with the plantation, you may have a serious issue. When you use the terms "plantation" and "former forced workers" in the same sentence or paragraph, the first thing that comes to people's minds are "black slaves". So, is the idea of the plantation theme that former black slaves, or the ghosts of former black slaves, are going to take over the plantation and kill everyone? I think if people think or assume that you are pitching black slaves as the villains then that could present some very serious issues. Obviously you're not suggesting that, but even tho, you might find yourself having to explain that.
The problem I'm seeing is that these themes seem to lack clarity. I'm not really sure what they are supposed to be. A good theme can be summed up in 10 words or less; ideally 7 words or less. The cognitive term is
"7±2". Our short term memory can only hold onto 7 chunks of information, plus or minus 2. That's the reason why phone number are only 7 digits long. Easier to remember and recall. In some parts of the country, like here in DFW, we need to enter the area code, but we tend to think of that as just another chunk, rather than individual digits. Iow, we think of it as "(972)" rather than "9, 7, 2". Some people even abbreviate it as "9)" to make it easier.
Hollywood applies this same principle all the time with the working titles of movies and their accompanying loglines (a brief summary of a film, providing a synopsis of the plot, and an emotional hook to stimulate interest). Very often the title of the movie and the logline is all you have to sell a movie before a single dime is spent (of what may be 100s' of millions of dollars spent). Very often a movie pitch will be nothing more than giving the movie title, the logline, and maybe answering a question or two, or mentioning an A-Lister to consider for the lead role, and that's it. Five minutes to sell your multi-million dollar movie with a few lines of info. And those ideas then need to penetrate into the ranks as the would-be producer you pitched to relates the idea to others and sees if there is financial interest. It's obviously a much more involved process, but you get the idea.
Likewise, your haunt's theme needs to have that kind of clarity. What is the logline for your haunt? As an example, there is an excellent haunt down here in DFW called "Zombie Manor". The idea is that a southern plantation owner back in the day had taken advantage of one of the slave girls, whose mother just so happened to be a voodoo priestess, and was none too happy about it. In retaliation, she cursed the entire plantation, turning everyone into zombies. It's a brilliant idea, and I've never see it done before, and that simple sentence tells you everything you need to know. The title and logline could easily be "Zombie Manor: Voodoo Priestess Curses Plantation", or something along those lines. Now, that's a logline that pops, and a haunt I wanna go see!
Also, again, there's nothing really scary about disgruntled workers and kids with parent issues, unless you are indeed talking about postal workers or the Menendez brothers. Remember, you are competing with zombies, psycho-clowns, vampires, werewolves, creatures from outer-space,
and I'm not even talking about haunts. I'm talking about the cinema on any given Saturday night, with shorter lines, cheaper tickets, really great concessions, guaranteed fun, and no stupid teenagers in masks spazzing out (unless you count a Star Wars or Star Trek premiere . . . and yes, I fall into both camps, sans dorky masks).
You are also competing against a lot of great halloween parties with lots of beer and chicks in slutty outfits. That seems to be a staple of adult halloween costuming these days, particularly at Spirit and other seasonal halloween superstores: "Sexy *cough*slutty*cough [random occupation or character]". Sexy nurse, sexy maid, sexy witch, sexy vampire, and so on.
Factor in other FEC's and amusement parks doing a special Halloween promotion, and that's your non-haunt competition. Add to that whatever popular haunts are around you within driving distance, and you can see how it stacks up.
So, that said, you don't want to be in the least bit maudlin in your theme choice. You want it to pop, you want people to get it right away, you want the concept to get into their heads like a thought virus, and you want them to become patrons, and also your best street-team, telling all their friends about your haunt.
Also, one of the best mnemonic devices, which helps promote awareness, is to connect a certain thought to a thought that someone already has, so that they can relate to it more easily. That's why themes work around popular archetypes that people can readily relate to, and also why you see these themes or motifs pop up in movies all the time. Themes such as Hospitals, Asylums, Circuses, Alien Invasions, Zombie Apocalypses, Victorian Mansions, Serial Killers, and Were-Beasts (which unfortunately may be going the way of Vampires as a theme). These themes serve as memes which people can readily relate to.
So, referencing the logline example above, for the first haunt, you might do a "Welcome To The Family" theme, which is basically what "Psycho", "House of 1000 Corpses", "The Devil's Rejects", and "The Texas Chainsaw Massacre" all fall under. In fact, here's an original idea which I don't think I've ever seen done before which ties in beautifully with WTTF and what you said you were thinking about doing.
The family of this manor (mansion, hotel, truck-stop, bed 'n' breakfast, etc.) are really big on family "inheritance" and "heritage" and "keeping it within the family", and it's the custom of this family that each generation of children, in order to "keep it within the family" and "keep the family strong", cannibalizes their parents when their parents reach a certain age. That's why the parents were never found. They were served up to their children to pass on the life essence to the next generation. Also, because they keep it within the family, you can also incorporate inbreeding. If you want to add a crazy cult religion to the equation, all the better. Make it some pagan religion that no one's ever heard of, or their own homespun cult that doesn't involve anything Judea-Christian. In fact, you could even add some Cthulhu cult type stuff, which gradually develops as you near the end. You don't have to go paranormal with it, or incorporate demons. Just the fact that this crazy family believes it is enough.
"Psycho, Inbred, Cannibalistic, Cthulhu-Cult Family Runs Truck-Stop/Bed-'n'-Breakfast." How's that for a logline?
What Bobby said.
Btw, even if you can work out the fog, still keep the misters and water effects. Clever idea and I don't often see it being done. Worth experimenting with if you can get it right.
C.