Hmm I can see now. There is no use to design a map without thinking of main story first.
Well, I still haven't go to details yet, but this is the plot i've been thinking of and im still overwhelmed with new ideas (also would love to know what you guys thinking about this):
Two brothers are traveling in a forest(or someplace else) and suddenly notice a strange, long forgotten facility.The brothers, out of curiosity, decide to check out the forgotten, abandoned facility. After awhile, because of the darkness and strange noises they are panic and one of them while running away went unconscious after hitting a wall, the other one's fate is unknown.
The game will begin after he wakes up. And in the first moments the player (meaning us) wont understand why he's calling for random person again and again. Only after awhile the player will find clues (notes that he's brother left in the floor\other places- still unsure what kind of clues) which turns out he's looking for his brother. While searching, he descovers the place was an hotel which shut down due to "budget problem" but something much more disturbing is hiding beneath the horrors of the facility.
It is said that after the hotel closed. The manager disappears. It is believed that he stayed in the facility, waiting.. for new customers.