General:
* Love
* Joy
* Happiness
* Peace
* Hope
* Kindness
* Compassion
* Honesty
* Integrity
* Courage
* Wisdom
* Patience
* Perseverance
* Resilience
* Creativity
* Imagination
* Trust
* Loyalty
* Respect
* Gratitude
* Humility
* Generosity
* Forgiveness
More specific:
* Empathy
* Optimism
* Enthusiasm
* Determination
* Ambition
* Confidence
* Self-belief
* Positivity
* Serenity
* Contentment
* Tranquility
* Wonder
* Awe
Related to relationships:
* Friendship
* Community
* Harmony
* Unity
* Support
Related to achievement:
* Success
* Excellence
* Accomplishment
* Progress
* Growth
This is just a starting point - there are many more abstract nouns that express positive qualities! It's important to remember that the meaning and impact of an abstract noun can be influenced by the context in which it is used.