You won't hear me defending TLA's filler, I dislike it as much as the next guy.
I have a problem with LoK's pacing because they really limited themselves with this 12 episode thing. With such a constrained time schedule, they really had to either sacrifice depth or breadth of material in order to fit it in; they ended up sacrificing a decent amount of depth to the characters and story. Amon as a character was really the only one spared from this, since they did such a fantastic job of building him up to this point. Almost everyone else has scarcely had enough time to build any character depth, in my opinion, which makes the first season feel rather rushed to me.
The fact that Amon is my favorite part of the series so far makes me really hope that we won't be seeing the end of him come tomorrow :x