I've been thinking about Warden and Barricade.
What if (and this is just tossing ideas around, nothing concrete yet) we merged the two concepts into a different game, where the players have some Warden-esque abilities (darkvision, mostly) and the ability to make traps, but instead of being survivors, they're professional monster-hunters? They wouldn't use magic directly like the Wardens did, but they would have their arsenal of equipment and the ability to MacGyver their surroundings into the sort of defenses you'd see in Barricade. The monster would have different weaknesses depending on what it is (like in Warden) and the protagonists would have to exploit those to kill it before it can kill them.
For example, instead of destroying random altars, you might have to find an altar placed by the monster before the game starts if it's a poltergeist, or you might have to track a vampire back to its coffin or what have you.
Combine that with giving players the ability to design their own maps and it might be better than Barricade would turn out on the course it's on now. Just some random ideas, but any feedback would be appreciated. The game is still early enough in the development process to allow for big changes, so this is still a possibility at this point.
Extended ramblings:
One problem I noticed testing Barricade was that people would find hiding spot and turtle, which would be fine for the monster (once it has a means to track the players), but the monster can only be in one place at a time, meaning the other players would be left bored. Having the players trying to directly kill a deadly juggernaut would force the players to actually work together as well as give everyone something to do.