Oh, I started reading manga after the first season, just couldn’t wait. :D I still watch anime because its WAY better animated, voiced and stuff. I havent started “final season”, I wait for a couple more episodes to watch in a bulk, but yea, some good stuff is coming. AoT is very well written and subverts expectations the right way. ;) I havent felt same suspense since “Death Note” or Naoki Urasawa’s “Monster”.
Although its called “Final Season”, I guess there is gonna be a part 2 which gonna air much later, because the first season of 25 episodes covers 8 volumes manga and right now anime still needs to cover more than 8 volumes, so be prepared for that. :) Or they can screw everything up and rush the ending…
There is actually some spin offs like light novels which they could have adapted between main airing anime. The “Before the Fall” light novels and manga adaptation (I havent read the manga, its covers 2nd novel) are actually quite good. They tell how the vertical maneuvering equipment was made.