Making the TC PC? What a strange thought. I guess quite a number of those who hold to the Commandments in their entirety strongly today would be the ones to not give a damn about PCness. (I could care less about PCness, too, for somewhat other reasons though.) I agree with the view that to even start "PCing them up", the references to the One God would have to go, which in itself would make the concept of the TC pretty much moot.
About the "needing moral guidelines", well, that's complicated. I don't know if others see it the way I do, but I quite sharply differentiate between morality and ethics, and I know that I fare better with an amoral stance than I ever did with morality. Morality, as I see it, is "considering something wrong because an authority (God, the state, your parents, whoever) says it's wrong"; ethics, in contrast, is "deciding whether or not a given action helps or hinders you to live the life you want, as the person you want to be, in a world worth living in". So morality requires nothing but obedience, while ethics need the philosophical leg-work to build up values to adhere to... or, polemically put: Morality = Ethics For Dummies.
Either way, there's a multitude of possible moralities or ethical systems, and I think it's good that there isn't a universal set of them, even though this means one system's virtue can be another system's vice.
Still, to someone like me, coming from a serious brush with solipsism in puberty, any kind of humane ethics (i.e., at the very least, one respecting basic universal human rights) still need a basis in faith in God... but that just shows that I, personally, am not fit to be an Atheist, at least as long as I'm unwilling to be a sociopath, too. (Not saying every Atheist is a psycho, just that I myself couldn't be one without the other. 😉 )