I don't think TLJ was terrible as two-face. As far as a villain goes, he was fantastic. It's the script writer's fault for writing 2 face like that. TLJ is a great actor, if they would've made 2face dark and troubled, I'm sure he would've nailed it perfectly and we'd be asking if Eckhart could live up to that. Schumacher wanted him to play it wacky and flashy and TLJ did that....wonderfully. I'm not at all a fan of Schumacher's version of two face, but I liked it for what it was.
Same goes for carrey, but I would've liked it more if they went with more of the opposite villain team. Carrey's riddler could've been like Gorshin and toned down a bit, but still a little wacky. And two face could've been the straight man, the tragic character. That way you got a serious villain and a funny villain working together, and towards the end they could've even turned on each other. But we got what we got.