Dr. Craig is a liar.

[Angrboda]

What gets me is the idea that a timeless, immaterial, omnipotent, spaceless being is somehow a less ludicrous supposition than an infinite past or something coming from nothing.  You don't solve an absurdity by proposing an even greater absurdity.  The chosen solution, this 'God', is more extreme than the alternatives.

That is a good point. However, no one is using the KCA alone to prove God's existence. There are additional reasons to think that God exists. 

Natural Theology:

• Cosmological Argument from Contingency
  
• Basis for Moral Absolutes
  
• Teleological Argument from Fine Tuning
  
• The Ontological Argument
  

With the exception of the ontological argument, these tend to devolve into arguments from ignorance, that we can't explain this or that paradox, therefore God. It doesn't take radical skepticism to doubt those conclusions.

Revealed Theology:

• The OT
  
• The NT
  
• Miracles
  

Revealed by God or by man? These have the appearance of man-made things and so using them as evidence for the same man-made things is circular. You're using mortal words to demonstrate the transcendent. It just doesn't wash.

Individual's personal experience

This is only evidence insofar as it is a reliable indicator of an encounter with the divine. It tends to be more likely an encounter with human psychology than an encounter with the divine. That makes it unreliable.

While you may debate as to how much evidence each gives, they mostly stand or fall together so if someone wants to say there is no proof for God, you would have to dismantle all of them to support that statement. I am sure there are some people here who think they can do that, but what it really comes down to is that it takes an extremely high level of skepticism to deny all of them. At that level of skepticism, you have to start asking if it possible to believe in anything.

It doesn't take radical skepticism to find fault with all these evidences, thus your slippery slope does not exist.

OR, is it more often the case that non-belief  is a result of an emotional response...perhaps because suffering exists or some related objection?

I can't speak for others, but I find your hypothesis self-serving and highly questionable. I think ultimately those who disbelieve come to the same fundamental conclusion: those things that are believed are absurd and unbelievable.