C&C:
...I've gotta agree with the comments regarding lighting and adding subtle environmental props on the walls and floors. The level looks very bland, unappealing, and boring as is. Try to make it look more like an actual hotel, and it will improve it dramatically.
I am puzzled as to why every skeleton is equipped with a firearm. Wouldn't it be more realistic if they were melee denizens bent on hunting you down, and ripping you apart? It's not to say that there couldn't be skeletons that do use guns, just not every single one...
Following your storyline, it would be much more suspenseful and realistic if the player had to use improvised weapons that he/she just happened to stumble upon. After all, why would a scientist be packing heat? Fists...an axe...a hammer...a broken piece of the helicopter...these would make it much more suspenseful, as Jack battles the skeletal horde. Finding a gun with ammunition should be a huge and surprising find, shouldn't it?
I think that you've the basics for a game that could be quite entertaining to play. Make some improvements in some crucial areas, and you'll get there eventually.
Thanks,
Seth Black