Notice that Jesus isn't saying that the sabbath is unimportant. Rather, he's pointing out its importance adds to the significance of healing the woman who has been crippled for almost two decades. As Sharon Ringe puts it in her commentary on Luke: "The core question is not whether to keep the sabbath, but rather how to keep it, and specifically, how keeping the day "holy" to God...."
Also note that the woman did not approach Jesus asking him for help. Rather, he saw her, called her over, healed her.
Which religious rules are we keeping but in the wrong way? Do we wait for people to come to us for help, or are we watching for opportunities to give help?
Further note the woman's reaction. As soon as she was healed, she began praising God. Do we remember to be grateful to the source of our gifts?