Thinking about ST PIC S1,2,3 it all blends together. I liked bits and pieces of a lot of it, but it was quite incoherent. S3 was confusing because I feel like I'm mixing up two seasons, but it's the writers that mixed up two Big Bads.
I appreciate a lot of what they were trying to do and all the elements were in place, but the ending of each season was quite, I don't know, abrupt and a fizzle at the same time. The S2 ending was a bit more satisfying than the other two.