I read somewhere awhile back in an interview with the show creator that each season would have a theme. The first season was infidelity and the second was madness. To me that makes Asylum make sense a little better; at least why it was so all over the place and over the top with aliens, zombies, Satan, Nazis, serial killers, a mad scientist, crazy Santa Claus, the angel of death, and a WTF Glee song. I didn't like the plot as much as season 1 but it wasn't as much a story as a snapshot of the asylum during the time period. I really enjoyed all of the characters more in Asylum than the first season and didn't find any of them annoying like the emo kid or the college student he was cheating with in the first.
It took me a few episodes to get into this season but then the middle was very strong. The last 3 episodes felt like they didn't know how to tie it all up. Just felt a little loose and that the climax was 4 episodes from the end.