7. Writing
The structure of 30 Rock could easily fall apart without the brilliant writing featured in the show. There are so many characters coming and going that without solid writing the show would be an absolute mess. Every episode regularly runs three or four storylines together and somehow makes each of them not only interesting but work flawlessly as a stand alone story. The first season was much more focused on Liz and Jack's relationship but once the writers started incorporating Kenneth more into the show then it really hit it stride. It's brilliant how the writers are able to weave every storyline of every episode into a seamless whole and make it look effortless.