The quiet section in Vermillion Moons, all the way up until the solo is awesome and very melodic to me.
Wanderlust is a wonderful mixture of melodic and more of his traditional style (also some absolutely beautiful melodies in the quieter sections).
I'd also describe Wrath of the Universe as quite melodic, not mushc "talking". But the melodies are weird and unpredictable. After so many listens, I can't sing along but I absolutely love them. It is again a nice blend of traditional Arch and melodic Arch.
Tethered is just beautiful all the way through.
Straight and Narrow is mostly what people don't like about Arch, with except for the pre-chorus and the chorus which could as well be Alder-era FW moments.
Pitch Black Prism features some of his best vocals, imo. Another song that mixes his beautiful sense of melody with his other more talk-singing style.
Never in Your Hands has some amazing harmonies.
Kindred Spirits... If you can't to listen to Arch because he's not melodic for you, I suggest you listen to this song and if you don't like it - I don't think you'll ever enjoy anything he does
There's no shortage of melodic singing, but it's rarely an entire song of what most people would instantly like in a melody. And I mostly don't care about Arch in FW, the only song I really like from that era of Fates is Guardian.