The other covenants are nice, I like the Kyrian's aesthetic out of all of them. I just felt that Night Fae had a more useful utility for me on how I play. I dont need a Mastery buff from Kyrians and I dont need extra Adds from Venthyr (can pull mobs I dont want). I almost picked Necrolords for the shadow DoT from Bonedust Brew. But Faeline Stomp, I feel like I would use in way more situations.
Feyline is nice because its solid AOE damage and also does aoe healing on a very short CD. I also use it as a pulling spell soloing. I can see how bone dust brew would be nice for raiders but it seems like felyline is pretty overall useful for all specs which is nice.