I used to collect the New Teen Titans comic books in the eighties. They started out with a story about Raven being the daughter of Trigon the Terrible, a malefic entity that had the power to destroy all of creation and make it into a Hell on Earth. He was incredibly powerful, essentially the ruler of Hell. How on earth do you make Raven into what she is on Teen Titans GO!? I've no idea, but apparently they did, and it seemed to work.
Those issues (drawn by George Perez with a story by Marv Wolfman) were some of the best I have ever read. They followed up with fifty issues of incredible storylines, introducing characters that became villains (like Terra) and dealing with real teen angst and some stories that were very similar to what we see in Riverdale (the Archie comics series on the CW). It was some very adult stuff. Furthermore, Perez started to change Raven's appearance in subtle ways after the Titans first encounter with Trigon the Terrible. Her face started to get longer, and she wore her cowl more and more to hide the physical changes that were happening to her. It was a thing that took many issues and went on for years, and it was so slow that you really didn't notice until it was pointed out in issue 50 when Cyborg was talking to Nightwing (I think) and showed Nightwing on the computer just how much Raven had changed in the years they'd known her. All of this (of course) pointed to something BIG that was headed their way.
There was so much character development. Dick Grayson (as Nightwing) had enormous emotional baggage left over from his time with the Batman. I could totally believe it when he said, "F*ck Batman" in the trailer, because this is obviously the way that the show's creators are going. And Princess Koriandr, a.k.a. Starfire, fell in love with him and the romance was great. Anyway, after seeing the trailer, I'm really looking forward to this series, and I've no idea why it's getting panned so much online. I think people somehow forgot that Titans is a DARK storyline. It isn't supposed to be campy. Raven's storyline in particular is the backbone of the whole thing, because it's her storyline that essentially dooms the entire world. No one can beat Trigon. In issue 50, when Trigon came back to Earth, he enslaved legions of superheroes. Superman was nothing to Trigon, nor was the Justice League. He's easily as big a villain as Thanos is to the Marvel universe (or on that same level of power).
Anyway, this post is just a little rant. Overall, I'm happy that the showrunner is taking cues from the Titans source material (the actual comic books) and not Teen Titans Go! I've put the trailer below if you haven't seen it. For what it's worth, I think the casting is really good. I just wish that the forces that decry DC for being "too dark" would just go away.