Well, that is kinda why I'm at least trying to go at it from another direction.
Thing is, while of course the skeptical atheist argument is correct, the thing that kinda nags me more is that even if you grant the existence of gods and all, the theist arguments are STILL utter nonsense.
Basically the most common theist argument is of the form of: <weak-sauce argument for some original maker or supernatural aspect> THEREFORE don't be teh ghey. Because that's what it boils down to, when one then goes some form of "and that is what we call God." (To borrow Aquinas's phrase.) There are a whole bunch of other attributes that are suddenly introduced by identifying it with any particular god, that just aren't in the set that was even invalidly supported. It's just pulled out of the ass.
I mean, let's even grant that there are gods, and they're unfathomable, for the scope of this exercise. Let's even grant that that synapse mis-fire is actually some being of light. Fine. But which god? Exactly what in that light says it's the xian creator deity, and not, say, Ra or Amaterasu? How do I know it's Odin, who'd reward me if I go die bravely in a shootout with the cops while raiding a bank, or the xian god, who, I'm told, would frown upon that?
Hell, even sticking to xianity and the topic of recognizing someone... How is the guy recognizing that light as the xian creator God, more right than the equally xian guy who recognizes it as St Peter (NOT a creator), because that's who they expect to meet them at the pearly gates? How does one support that it's one and not the other?
The whole argument is one big ball of nonsense even IF I grant the existence of gods and their complexity. I can grant all that, and their argument still won't come anywhere NEAR supporting the conclusion. They're still basically left holding an empty bag.