You say you lack imagination. I disagree. This image shows imagination. The moon is great. The shading of the pinnacle shows a good start. There is a photographer in my area who only takes pictures of concrete sidewalks. He walks everywhere looking for the right photo. That is not imagination, just perseverance.
Not everything turns out the way you may expect or want. Real landscapes are filled with errors and sometimes are just ugly. I try to make the best of my disasters with Terragen 2. Sometimes just changing the lights or sky works. Other times I'll throw the mess into my paint program and make an abstract of it.
Keep trying. The more you have learned, the more your imagination can flow. If it gets frustrating, come back tomorrow and try again. I also do this.
Oops, responded to the wrong thread. I was referring to another thread you posted. (Lack of sleep, sorry.)