Lexa's fight scene was great, both in the way she fought and in the way she handled her victory, by getting rid of one enemy and turning another one into a loyal subject with one spear throw. Just another reason why she's the Commander.
Bellamy's decision to side with the Farm Station people is disappointing because it's so stupid. They are on the cusp of a lasting peace treaty with the majority of the Grounders, which will give more protection than anything his crew has seen. The Ice Nation people are just a small splinter group who can't accept change, and the Farm Station people are exactly the same way. Bellamy should be smart enough to see that.