We actually got to see the kiss! I expected them to cut to another storyline.
Those rooting for Gil should take comfort in the fact that in melodrama such as this back and forth among the rivals is essentially. If Tarvek didn't have a chance, where would the tension be?
But defending Tarvek. Tarvek grew up with a typical scheming Mad Boy family centered around the prospect of world domination. Despite that, his goal to become the Storm King was actually about trying to make the world a better place. Now that he has found Agatha, he is actually trying to become a better person -- as witness his dragging his wounded out to rescue them when any actual amoral Mad Boy would have left them to their fate. And Tarvek doesn't even try to justify with some self-serving excuse. He just grumbles and then does it.
Gil is the idealist struggling for identity because he sees the disconnect between his ideals and his father's methods but also recognizes that his father's methods are effective. Tarvek is a rebel looking for a cause. Both of them found Agatha, and each other.
It's one of the reasons I stick with this series. The characters do grow over time.