that style was originaly created on Providance, I adapted it to 2k1 later on after providence died with permission.
Though I see alot of people use styles and techneques I made a while back, flattering
The levels are really nice, creative and well layed out.
But from a picky perspective.
level 1
The latter does not fit in, I sugess recoloring it. The dirt has a repeditive non organic feeling to it. The rug that connects the chair and the table is not noticable, it would be good for it to stretch out a tile to the left and make it look more like a rug.
It might be arguable to add more content inside the level itself. chairs tables. Good subterarian feeling. To create more of a dark diffused feeling, make the lights 2x bigger, but twice as dim, use light4.png with .1 alpha in the bottom area witht he same light colors at zoom 2 or 3 to create a diffused light effect. Same with top, but dimmer to suggest a mild reflection and bleeding from downstairs.
Level2
I'm not liking this one as much. I suggest adding a bottom tile to the "marron" table type outlines of the supports to suggest depth, as well as something underneeth the wooden trees. The floor is not in good contrast hue wise with the rest of the level, as well as the bed color, the stairs dont suggest depth at all sadly. Do the same thing with the rug as with level one, expand it to suggest its a rug, oh I noticed not alot of content, its a template I forgot

, I like them, though still a bit plain
Heres some inspiration if you think you need it: