I guess I'd also add that in the general Christian view, the specific, older-testament-era laws around the sabbath had a meaning, but they were really pointers to higher laws and concepts rather than, or possibly in addition to, being materially meaningful standalone practices. And as you rightfully point out, those "little laws and practices" were also subject to a higher law. I remember when I lived in Japan, I was working outside as very hungry young missionary one day and a kind old woman grabbed some fruit and a bag of chips off of her family altar and gave them to me, demanding that I eat. This had similar significance to me and is an experience that's very close to my heart.
IMO sabbath observance a great practice. There are few things like the feeling of a day that is uninterrupted by work concerns. And going beyond the limitation to what we _don't do_ on that day, it's also a day that's set aside for meditation, big-picture thinking about life, spirituality, and connection with the universal. In the past I let it slide a lot more than I do now, but in the past I was also a much less-healthy workaholic.