Connor's my favourite of the three. His storyline is also my favourite. I dunno, I just really like detective stuff, and I love Connor and Hank's chemistry~
Kara's story isn't my cup of tea, but I can see why people like it.
Markus' story was just boring until he became FRICKIN' ROBO-JESUS. Things from then on were definitely much more interesting, for both Markus and Connor.