Being an agnostic would be the only true rational belief, relying on no faith of any sort. Atheism takes work, almost as though there's an emotional need to be against something for no real purpose.
Only in areas where applicable. Such as how it was illustrated at the top of this thread.
The Hitler comment had flaws, but extrapolating its posting to be proof of intellectual capability is a reach. Darwinism is and always been a core belief that underpins all eugenics, including Hitler's drive for the creation of a master race. A response to Hitler's actions, the consideration of forced sterilization of Germans after WWII, because Germans couldn't be trusted to refrain from starting huge wars was a product of similar flawed thinking.
Not a flaw.
Closing oneself off from ideas based on a belief is a flaw.
However, I can only be proven wrong, by divine intervention. For now.