To clarify and deepen my understanding of the Heart, I pondered the following comparisons with similar and/or opposing cards. Maybe my comparisons will inspire you to make your own!
Relationship
Heart: A loving relationship - possibly romantic.
Ring: The commitment part of a relationship - any type of relationship; could even be a work relationship.
Lily: By itself a purely physical, sexual, relationship - could be respectful or exploitive.
Positive Emotions
Heart: Any positive emotion that is related to love: all types of love itself, kindness, but also tenderness, compassion, forgiveness etc.
Bouquet: Any positive emotion that is related to positive give-and/or-take situations: cordiality, thankfulness, appreciation etc. Also: admiration.
Sun:
Any positive emotion that is related to happiness - joy, mirth, ease, having fun etc.
Openness
Heart: To be open emotionally - to let others touch you emotionally; to be of a gentle, yielding, soft disposition.
Key: To be open in general - open to having new experiences, to trying new things, open to new ideas etc.
