Marvel's Daredevil: 31 Easter Eggs You Probably Missed
11. Marked For Death
There are significant hints that future arcs for the show will be heavily influenced by Frank Miller's arc surrounding Marked For Death (not the God-awful Steven Seagal film of the same name).
That would make sense, especially as it would allow for the introductions of Elektra and Bullseye, which would make for a seriously compelling second series.
All of the references to Miller's early issues, including Melvin's mention of Betsy Beatty and the seemingly innocuous lesser characters who appear, suggest that those early issues are important. If that is the case, and Bullseye is introduced as well as the Hand and Elektra, it would be a strong move to build on the first season's success.