It's funny you say that, because I thought season 1 was weaker than some of the later seasons. Content wise season 1 was the most interesting, but I don't think the show had yet hit its stride in terms of story development, etc. Each episode seemed to try to weave in subplots but never really generated a balanced narrative fabric. By season 2, though, each show really seemed to cohere as an individual unit and as part of the season-long story.
Of course, some of this may be a result of doing some necissary background work in the early going, but generally speaking, season 1 strikes me as the the most likely shows to introduce a character, develop him quickly and artificially, and kill him or otherwise take him out by the end of the episode. Later seasons, with more already developed strains and characters to work with, I guess, seem better paced.
I dunno. That's just my general impression.