Thanks for the reply! I agree with everything you said. I usually end up producing stuff like this--not very melodic. I'm trying to work on that, but I lose direction a lot. I also gotta agree with you it doesn't fit the poem very well. That wasn't exactly what I was shooting for, but I can see how I could have made it a little more relevant to the poem. I mostly wanted to convey death. One thing I thought about a lot--and something that especially inspired the epic moments--were the lines in the poem that talk about the Earth being man's great sepulcher and the mountains, valleys, planets, and stars decorating his tomb.
One day I think I might like to write a more suiting choral work actually based on the poem. But I really dont know much about writing for voices--or for a lot of things for that matter. I'm still trying to learn a lot about music.
Anyway, here's a second version where I added some more to the organ part and tried to make it a little more substantial.
thanatopsis2