Rescued from the Scrappy Heap: As one fan once said, "UF is where characters go to become awesome again after their original writers forget how to treat them right." This is a significant reason for the existence of the Legacy of Korra arc in Future Imperfect. If Gryphon's episode commentary in the Eyrie forums is any indicator, he felt the need to try to get the show itself out of the heap.
Some Anvils Need to Be Dropped: Time and again, Undocumented Features shows us that redemption is always possible, even for those who are perilously close to the Moral Event Horizon. And often, all it takes is for the villain to choose to walk away and try to make amends for their past mistakes. Moreover, forgiveness can be difficult, but being able to forgive is a good part of what makes the characters heroes. Without forgiveness, the galaxy would fall into chaos — or perhaps not exist at all (just imagine the consequences if Gryphon and Kei hadn't forgiven each other after the Exile). And most of all, they show that redemption and forgiveness are freakin' cool.
Ultimate Showdown of Ultimate Destiny: Fortress Maximus vs. Surtur. Imperial Star Destroyer vs. the Macross. The Big O vs. an Evangelion. The list goes on and on. Got a favorite? It's probably here somewhere. Or will be.
Wangst: The main weakness of the early Core stories, especially Kei and Yuri's disappearance in UF1, most of the plot of UF2: The Long Road that resulted in the entire cast becoming immortal, and the downfall of the WDF in UF3: Out in the Cold.