Nope, I don't regard any Trek as "purer" than the rest whether TOS came first or not. I watch them all, I see the flaws in them all, and I see great things in them all (the amount varies, but each one had them). I don't see the point in wasting your time over what is and isn't "pure" in a continuing series set over a lengthy time period, I mean the whole point of having a setting like that is growth, change and variety.