So basically there is a bunch of unknown stuff that no one could claim to know, except you who knows it.
In all seriousness though, I think most atheists are fine with the concept that there may or may not be some higher power out there that we don't yet understand. They're guessing one way and fully respect those guessing the other way. My wife and I are this way. I'm an atheist. She doesn't believe religion and their take on things, but she believes there is some kind of higher power out there at the center of things that she calls God.
It's the bearded sky man and all the horrific and contradictory bible mumbo jumbo (which often shapes their policy decisions) where people lose them.
I'll sit here all day and have a rational discussion with someone about the kind of stuff you are talking about. But once we wander into how those two penguins walked from Antarctica to the middle east to board a wooden boat to ride out the storm while that "loving" god mercilessly drowned a bunch of crying babies in their cribs prior to wandering back down to Antarctica and re-populating their species with some sweet golden incest....Well, don't expect me to take that any more seriously than you would if I proposed that Harry Potter's Uncle's Ghost created the universe when he mixed an expelliarmus charm with wingardium leviosa while using two wands made from the same Phoenix's feathers.