Are Atheists using Intellectually Dishonest Arguments?

[Amarok]

) Atheists often suffer from a "persistent inability or refusal to distinguish God from a god or gods"

Their is no difference. Theists are the ones engaging in special pleading by asserting their is a difference  

2) Atheists often presume  "belief in scientism, the logically incoherent claim that 'only scientific knowledge is valid/real/genuine knowledge'

Bullshit . Accepting that science is the best and firmest ideal of knowledge is not saying it's the only.  

3) Atheists often engage in "persistent use of the burden of proof fallacy, that is, the rhetorical trope which combines an argument from ignorance (“my position is the default position,” i.e. “my position is true until proven false, so I need not argue for it) with special pleading.

No we don't. Pointing out you have asserted a claim without supporting it . Thus i will accept the claim . Is not a claim that a position is true . Only that one position remains unsupported .