I would only add a border if you need to make the crib quilt larger, can't tell from the picture the size.
A good size is 35 X 45 for a crib quilt. I would use a nice bright childrens print in yellow, green or purple for either sex.
If you add a border, make the binding the same as the border. If you don't add a border, use a bright solid fabric in green, purple, red for either sex. For quilting on a LA, I would use a meandering pattern so it doesn't take away from the design of the quilt.