$14 isn't bad for a complete game free of microtransactions, especially one with as much content as FFT.
If that's too much, but you don't like free to play economy stuff like gacha (I agree with this, BTW), then I suggest emulation. You can get ppsspp and Joan of Arc or Ogre Battle, for instance. Both are great games, full of the tactical goodness you're looking for.
This is crazy left-field, but I always recommend Ranma 1/2 and Urusei Yatsura. They aren't, like, a lot like what you're asking for, but they're both absolute classics of manga and had an incredible influence on shonen manga the came after them. Both are upbeat, both are funny (especially UY) and full of action (especially Ranma), and are just generally great reads.
If not that, Assassination Classroom is pretty amazing, and maybe closer to what you're asking for.