The fact that Ethan and Benny have come up with lightsabers thatwork! At least against vampires.
With said lightsabers, Ethan strikes Jesse's throat.
Erica and Sarah defeating the sun queen and saving the Earth from being incinerated.
In the season two finale, Ethan taps into the mind of the Big Bad Stern who tried to kill all vampires in Whitechapel, (and even before The Reveal his students didn't like him). Ethan tells him he is weak, and his only hope for power is the Lucifractor. Stern basically get's pissed and absorbs the power of the Lucifractor, which results in an explosion, likely killing himself.
Ethan and Sarah going on their date in Pt 1 of the Season 2 Finale.
Benny's grandma telling Ethan and Sarah that regardless of what's going on, they care about each other and Sarah is the one Ethan wants to protect most.