I used BM Saybrook Sage in my living room back in 2004. Are these colors coming back?

Accent walls can work, but you need to tie that color into the overall design and not just add that color on one wall and have it not relate to anything else.

If you want to add color to your family room you might want to add a colored/patterned accent chair(s), colorful pillows, colorful art and/or colorful rug.

You haven't shown the room, so hard to give any specific suggestions.

I was wondering that too - if sage looks very outdated. I do have green for an accent color in other rooms ( pillows, blankets, etc ) so hoping painting one wall will look okay.