mellow

To make or become soft, gentle, or more pleasant.

"Time mellows the flavour of cheese."

Calm, gentle, and relaxed, often due to age or experience.

"He became more mellow in his old age."

Soft, rich, and pleasing to the senses; not harsh or bright.

"We enjoyed the mellow evening light."

Fully ripe, sweet, and rich in flavour, often referring to food or drink.

"The wine had a lovely mellow taste."