Has anybody put together a table or rule of thumb for average challenge rating for a given character level? I realize that there is probably some variation based on class features, optimization, etc, but is it possible to say, "A 7th level PC is usually CR [x]?"
I ask for situations where I want to create an NPC using player class guidelines, but don't feel like going through all the steps of calculating a given creature challenge rating. Which is maybe dumb, but, whatever. I'm fine with being off by a CR, because I tend to eyeball CR and encounter balance anyway.