General synonyms:
* Amazing
* Brilliant
* Excellent
* Fantastic
* Splendid
* Terrific
* Superb
* Magnificent
* Outstanding
* Remarkable
* Impressive
* Delightful
* Fabulous
* Marvellous
* Exceptional
More specific synonyms:
* Enchanting: Suggests a magical or alluring quality
* Exquisite: Implies great beauty and refinement
* Exhilarating: Conveys a feeling of excitement and joy
* Extraordinary: Highlights something that is unusual or exceptional
* Heavenly: Suggests a feeling of bliss and happiness
* Marvelous: Emphasizes a sense of awe and wonder
* Sublime: Describes something awe-inspiring and majestic
* Exultant: Implies a feeling of great joy and triumph
Informal synonyms:
* Awesome
* Rad
* Cool
* Sweet
* Epic
The best synonym to use will depend on the context and the specific feeling you want to convey.