General:
* Agreeable
* Delightful
* Enjoyable
* Nice
* Satisfactory
* Gratifying
* Appealing
* Charming
* Delightful
* Lovely
* Wonderful
More specific:
* For a person: amiable, affable, congenial, cordial, friendly, likable
* For a place: inviting, cozy, welcoming, comfortable
* For an experience: satisfying, rewarding, fulfilling, enjoyable
For a negative connotation:
* Mildly positive: Tolerable, passable, acceptable
* Insincere: Fake, superficial, insincere
The best synonym to use will depend on the specific situation and the nuance you are trying to convey.