Without claiming to know if there is a God, or what the qualities of such a God might be, we can use only reason to propose an entity that is outside of human understanding, perhaps in the way that you describe. It's very simple!
Well as they say, of that we know nothing about, we must remain silent. So yeah, if you propose some entity or concept that is by definition beyond human understanding, then I've nothing to say on the matter.
If we are entirely clueless about many things, then entities that make absolutely no sense to us, such as you describe above, are entirely possible, indeed probable.
This I don't agree with. I don't think you can speculate as to the likelihood of things we know nothing about without contradicting your principles. There may be any number of things completely unknowable to us out there, and then again there may not be. The Christian God is not one of those things, regardless.
Ok. No problem here either. In the end, I have no basis upon which to debate your beliefs.
Well, now hold on a second. We began this discussion with you saying we can't apply reason to the big questions of religion. Now it seems that point doesn't apply to Christianity. Well, that's a third of the world's population. May as well add the Muslims and the Jews, they believe much the same about God, so that's another quarter. Buddhists and Taoists and such I don't think are in any conflict with you, that's what... a sixth of the world?
So when you were saying what you were about the futility of reason in examining religious questions, did you in fact just mean the religious questions of Hindus, atheists, and a few Christian mystics? If so, then it seems we're in pretty much perfect agreement- Hinduism and Mysticism have always seemed pretty incoherent to me for basically the reasons you've described, and the strident atheist makes a fool of himself whenever he tries to precisely define that which he insists there is no-such-thing-as.
But an indictment of reason and religion that applies to maybe 20% of religious people seems odd to me, especially when you won't find that 10% here.