Examples: Sam Harris, Richard Dawkins, Robert Sapolski, Neil DeGrasse Tyson, Dan Dennet, Christopher Hitchens, Bill Maher, Lawrence Krauss, etc.
It might almost be cliche but I am a diehard Sam Harris fan. I love his well put together extemporizing as if he's reading a novel and his large vocabulary. I don't agree with him on everything. I'm no yes man, I mean, I'm even Pantheist and will disagree with him about the existence of free will saying, "nah, it's something deeper than that man," and claim turtles all the way down until there is concrete evidence for the non-existence of free will. I know a decent portion of the data that would lead him to deny free will, but as I've said, I'll willfully be stubborn here for hard proof. I agree with him however, that we are all downstream, as in we are all somewhat a product and responsive to our past. However, I find that how we may presently reflect on ourselves and our history in any way we see fit if we are able to play with perspectives that may have drastic affects on how we carry out the future. To get a little deeper, but I won't go on about it, I'll cut and paste a bit of my consolidated knowledge on the subject... We can be nothing but a response to our environment which conditions our subjective experience and knowledge to which we are reflective; determining the epigenetic expression of our genes manifesting conduct for which we create meaning-making to reconcile a possibly locked in worldview that is formative of our adopted beliefs and values which are saliently operative, all the while working with the human condition and the desires and needs of the body inside pain/pleasure parameters. As we seek that which is pleasurable and avoid at nearly all costs true pain.
Of the four horsemen, I think Harris is more open to new ideas. Dawkins, Hitchens, and Dennet more set in their ways, though they all had useful perspectives. Love Sapolski, and have great respect for Krauss, but my current fascination is with Jordan Peterson. I don't love everything he says, but the dude is one complex and nuanced thinker.
Hitchens was, by far, my favorite Atheist/Anti-theist intellectual. His wit was like a finely sharpened scalpel used to eviscerate any would-be theistic apologist. Actually I like and respect all of these individuals. I'd like to throw in Aron Ra and Matt Dillahunty to my list of non-believing intellectuals.
Love Neil DeGrasse Tyson, definitely one of my favorites but I love to listen to others as well and while not a person, I stumbled on the Clergy Project and love listening to former and current clergy who lost their religion tell how and why it happened.