My favorite anime would be Neon Genesis Evangelion (the original 1995 series).
I appreciated the deconstruction of mecha anime cliches and the themes of psychological trauma. For the infamous conclusion, I prefer the manga's ending. As for the Rebuild films, I loved 1.0 and 2.0, but 3.0 and Thrice Upon a Time lost me. Music-wise, "Beautiful World" is well, beautiful, and "A Cruel Angel's Thesis" never gets old no matter how many times it gets remixed and covered.