Is nihilism the logical extreme of atheism?

[genkaus]

My knowledge of God isn't flawed.

This statement presupposes 3 things:
That a god exists.
That you know things about him.
That your knowledge corresponds to how he really is.

Without proving those three your statement is meaningless.

My knowledge is however limited, as we can't know all there is to know about God.

Being limited can be considered a flaw.

We can make decisions based upon this reality being a just one, assuming a just God making it so. We know this reality is unjust. We witness that most days.

Contradiction alert: If we know this reality is unjust and we make decision on the assumption that it is just, then we are essentially making decision based on a lie.

You and I know what justice would look like. Our perception of reality is shaped by it.

Yours maybe.

You're accusing the mainstream church of having a conflicting understanding of God, where the mainstream church maintains what it decides is a consistent understanding of God, all acknowledging the Nicene creed. You're going to have to be specific and state what exactly you find to be conflicting. We have a few different flavours of mainstream Christians here who could confirm either their connection or disconnection with me.

The bolded statement is sufficient to establish conflicting understanding of god. FYI, consistency on a subject is determined by logical coherency, not popular vote.

Belief shapes our understanding of reality. That applied to everyone.

Not everyone - for most here reality shapes beliefs.

Any flawed thinking is simply flawed thinking. It has no bearing on the differing realities perceived either side of justice.

It does if the assumption of justice is a product of flawed thinking.