For me vocals become easier the more structured my concept is.
If I start from nothing it usually goes beat, bassline, chords, melody, vocals, embellishments.
If you conceptualize an album title/concept and make up song titles that adhere to the theme it's easier to start flushing out individual subthemes or sidestories.
In my opinion the good music and songs already exist in potentiality it's just up to you the musician to uncover the tone rows and melodies that get your point across most concisely.