Richard Morgan invited me to post in this thread and I'm happy to do so. I've been an atheist for some 40 years or so. Brought up by Anglican parents who weren't overly religious (though they did send me to Sunday School) I was belatedly invited to be confirmed into the Church of England at about age 14 or 15. I say belatedly because by that time I knew I no longer harboured the faith of my childhood and had prevaricated when the suggestion was put to me. Nevertheless, my mother wanted me to be confirmed and I agreed to be tutored one-on-one by our local vicar. We had some interesting but fairly fruitless discussions, and after about four of these sessions he said he was prepared to confirm me despite my professed doubts. By that time I was certain I could not in all honesty be confirmed, and found his willingness to go ahead anyway somewhat disingenuous. I admit that this incident did cement my unbelief at that time.
After that background, on to your questions about what I might find compelling about "God being real" and "Jesus being God". The latter depends on the former, and as I have major problems with the idea of God being real the question of whether or not Jesus is God doesn't arise for me. First I must consider what we are to understand by "God" and "real". If by "God" we mean an intelligent creator of the universe (and by "universe" I mean everything and not just a subset universe of something else), I can conceive of a kind of power or essence in which the universe came to exist, but I find the notion that this power could be in any way personal or intentional to be untenable. By "real" I mean in actual existence — probably some kind of physical existence, because though I can imagine the existence of a god, and I believe my thoughts are "real" in the sense that I do actually think them (and so my thoughts do actually "exist"), they don't have a physical existence in the physical world, beyond being information in my brain. Let me say that though I can conceive of such a God-essence, I've yet to see any compelling evidence for it, and have no reason to suppose it actually exists.
This is a long-winded way of coming round to the statement that I find the Abrahamic God of the major monotheistic faiths completely illogical, ridiculous and unconvincing. I can't conceive of anything that could convince me that the God of the Bible is "real". (I have, however addressed this elsewhere.)
I'm aware that many Christians claim to have had personal experiences that convinced them God is real, but as I've had no such experience I can't offer any opinion on whether such an experience would convince me.
There are lots of arguments for the existence of God, but I don't find any of them convincing — at least, not the arguments I've come across; I'm happy to consider others. I don't think many Christians find these arguments convincing either, using them merely to bolster the faith they derive from personal experience. So we reach a kind of impasse: the theist is convinced by personal experience, but knows that this is unlikely to convince someone who lacks such an experience, so he or she resorts to the well-known arguments for the existence of God, despite not finding them particularly compelling. It's hardly surprising that the atheist finds them even less compelling.