Most music outside of the Western classical realm has heavier reliance on improvisation. Music notation there is often simplified as a result. "Chord charts" or

Most music outside of the Western classical realm has heavier reliance on improvisation. Music notation there is often simplified as a result. "Chord charts" or "lead sheets" are common in jazz where only the melody is notated in standard Western notation, together with the lyrics and the chords, with the arranger or players responsible for the rest. Pop musicians sometimes just get by with Roman numeral chords over lyrics if it's a song they've heard before that they are covering. From my perspective, excluding length and rests is problematic for this notation, though. Even lead sheets had these. Rhythm is such a huge part of music. This would be a difficult system to convey even a simple melody line to a musician unless the person also hears the song. (If this is intended to be more like tablature where this is typically what happens, then yes, it's fine.)