Is the following sentence grammatically correct in regards subject-verb agreement?
One of the main facets of the soul is the feelings humans treasure above all: love and compassion.
The sentence seems to retain its meaning when flipped around, revealing that "the feelings" might be the true subject, and indicating that the verb form "is" could be incorrect. For example:
The feelings humans treasure above all -- love and compassion -- are one of the main facets of the soul.