2 mmol´s raise from the number before the meal is what I was taught was okay...
what is more important is that the number levels down into normal area at the latest 2 hours after the meal...
we are actually all very different, some have a much more severe insulin resistance and some can´t do the very low carb eating style.
you have to be your own Anchor, and decide what is your personal goals.
I think you should mostly focus on any development that goes in the right direction.. just decide your own main focus...
as more people in here has said; this is not a sprint this is more like a lifelong Marathon... and we (almost ) all fail once in a while and have better and worse periods where our efforts varies