After reading this article I dug through battle.net to try and find your map. Lo and behold after 10 minutes of pressing "show more" I came across it. A truly excellent game that is fun and innovative. There is no reason why this shouldn't be in the top 10 in popularity (if Blizzard didn't create a mess of finding custom maps anyway). The fact that you can't even search by title and author is pretty sad. Hopefully they will fix this soon because what's the point of having an epic map editor if at best you only get access to the top 20 most popular maps and the rest are buried away from sight?
Here are my thoughts on the gameplay:
-The atmosphere is amazing. I especially love the blinking lights and falling water. These are great ways to "spook" you into thinking the killer is close.
-I don't have a lot of information on the map itself, but I assume that there are a lot of secrets that both the killer and the player can take advantage of, ie: it rewards you for exploring and playing the game multiple times. This is definately important to keep players coming back to play your game more than once.
-I definately like the fact that killed players are able to contribute to the game by becoming ghosts and scouting out where the killer is.
-Music is awesome and adds to the atmosphere.
1) Like many have mentioned above the main threat to your game is boredom after playing the game once or twice. There are very few actions you can take as a player or killer which reduces replayability. There must be more strategies that you can employ or else the game will become stale very quickly. Coming back as a ghost is definately a good choice but it only partially solves the problem. Many players will still be bored and leave after being killed.
Here are a few suggestions to help make the game a bit more strategic and more replayable.
A) Make it so that there are traps already set in the environment. These traps will NOT be deadly. At most they will delay (block a path and make them take a detour) or stun either the player or killer (trap them in place or knock them out for a few seconds). Create a variety of traps such as ones that automatically trigger when you get close to them or ones that require TEAMWORK. Such as requiring two players to set up before it goes off. Ie: a great idea would require 2 players to be in certain positions close to where the trap must be set off. This is dangerous because the killer can find them before the trap is released. Traps should be placed in locations that 1) surprise the player/killer if they've never encountered them before 2) are difficult to avoid even if you know the location (ie: at choke points and entrances).
This increases strategy because: 1) You can now try to lure the killer into traps instead of just running away. You need to be more mindful of the environment. It promotes teamwork.
B) This one is quite difficult so I'm not quite sure if it could be implemented or not. My idea is this: When a player dies their body stays behind. Other players that are still alive can go back to the body and drag it to particular parts of the map where they can revive the player. The added difficulty would be that players are unable to run while carrying the body so there is a large risk involved. This is great because if you get killed there's an incentive to remain because you might be ressurected. It also adds another layer of strategy: have players distracting the killer while 1 or 2 sneak off to revive other players that were killed before.
C) Have your score increase more quickly when you are alone. The reason is because the game should put a lot of emphasis on teamwork. You should be working with the other survivors to use hit and run tactics to set up traps, rescue dead survivors and stay alive yourself. It would be incredibly boring if you just huddled by yourself all game waiting for the killer to cross you. HOWEVER, I also understand that staying as a team would dampen the atmosphere and impact of the game. Giving bonus points for staying alone encourages you to work as a team sometimes and play by yourself when the situation suits you.
D) Give ghosts a bit more usefulness other than scouting. My idea would be to give them a skill that costs energy (and energy would recover over time). This skill would be the ability to materialize for 3 seconds before becoming invisible again. What this does is play mind tricks with the killer. Ie: There is only one last survivor and the killer is getting close to finding him. You are already dead and materialize close to a different entrance to try to lure the killer away. Now you have two incentives for not quitting once you die: 1) You can actually help save other survivors by materializing and fooling the killer into following you. 2) You have the chance to be ressurected again. 3) You can help direct players away from the killer.
E) Give the killer the ability to set traps. This ties as a counter to (A). (A) will be mostly used by the players (if they are smart and don't run into them themselves) and are static. The killer on the other hand has the ability to place them anywhere and is limited to x number at one time. The trap can be seen if you're careful and not dashing all over the place. The trap functions as a "hold" and alerts the killer to where it was set off.
F) UNLOCKABLES. Woohoo. Another tool for replayability. Right now all of the players have the same model and it is quite boring. A good way to keep players coming back to play your game would be to have unlockable costumes based on the player score. Rack up enough points that saves after each game to unlock costumes. This game should encourage players that play the game often. Unlockable costumes as well as knowledge of the map (such as pulling off LOLworthy traps on your opponent) is one way to keep them happy.
Whew. Sorry for making that so long. Just shows how much I appreciate what you've created!
As for your current problem with popularity and getting people to play the map, I would suggest this. Get a bunch of people who would like to help you (and I am definately interested in helping in any shape or form) can be friends, people you've met online, etc. And right now just focus on having 4-8 people that can help you with testing the map and improving it for updates. So basically playtesting if you don't want to trust them with the map. Or more if you're more comfortable. The fact that you have 4-8 dedicated playtesters playing with it and suggesting improvements makes you feel a whole lot better about creating something than just having it sit at the bottom of the ladder doing nothing.
Improve it either with your own ideas or with some of the ones I've suggested. Play test it with that tight group of people until you think it's ready to be released. I would then inform the community to create anticipation and get people pumped up to play it. Create a new version of it on battle.net. It should shoot skywards in popularity.
Best of luck. And let me know if you need any help whatsoever. This definately deserves to be worked on!