Hey, everyone has different standards. By my standards that's a good A1c, especially since you have not been dealing with this disease for that long! And .2 is hardly a "slip" worth worrying about at all. Of course it's always onward, ever onward, set your sights higher and reach for it. Like me you could perhaps be aiming for low 6s the next few A1cs.
You've invited a whole lot of opinions

. The most important question is what you think and feel about it. If you are happy with yourself for maintaining a certain level of control then BE happy.
What you say in your blog about being a math person and realising you need to stop expecting perfect diabetes numbers in the same way as math, you are bang on, in my opinion. Congratulations on gaining this awareness, it's something that often has to click inside someone before they can relax about the whole thing.