Steins; Gate is easily one of my favorites. Totally absolutely loved it. The movie wasn't really good compared to the anime and I didn't watch Steins;Gate 0 I'm trying to find some time for it. I'm stuck with Tales of Zestiria X.
Gankutsuou is superbly and uniquely stylistic and the story is complex and gripping. The music does an amazing job too. You'll love it :)