Thanks for the quick responses. The first two pictures are actually my single player world where I test out the structures first to see how they look. The houses just happened to be in the background. The texture pack is chroma hills (though the cobblestone and stone brick is persistence). These are the houses in the server real quick if your wondering. I try not to take too many pictures of the structures in the server as some of it is not original, though all the houses are.
No world guard. So I took the world folder from my server and replaced it with another server, and I had the same problem. Can the world itself be corrupt somehow?
Not to bring up my topic again, but I tried a few things that might give some insight. I reset my world on my server, with all the same mods and everything and monsters seem to spawn just fine (a little bit too much, but that's great). Then I backed up my world and all of a sudden not spawning again.