The first one could benefit from a more structural approach to composition. Think of the path the eye takes when looking at the elements of the image and try to make it as smooth a journey as possible. It's kind of off-balance, with all the interesting details falling middle-to-right and a lot of empty cliffside on the left.
The second could use more accurate use of perspective. The roof seems to be getting larger the farther away from the viewer it is.
It took awhile and I am sure with a better program I could do it better but here is what I think of as
Longing for fresh air
It is inspired by the Daemonforge and some writing I have been doing for the setting lately. It is one of the Gates of Numer (DF hell) and an annon. fiend.