Take individual pictures of your family members and have large prints made in black and white. Add to the size of each photo by adding a photo mat, then frame them in inexpensive black frames and hang them in a row across the wall.
Use floating shelves hung at various heights and topped with photos, vases, ornaments, books, candles, or mementos.
Use plants to fill in empty spaces. You can place potted plants or succulents on floating shelves, use planters or hanging baskets made to attach directly to the wall, or make a DIY vertical garden out of an old wooden pallet