Well if everyone saw the same appearance then you'd have intersubjective confirmation of god's existence. The next question, is does god make it clear WTF he actually wants and his rationale for same. Then we could not only agree he exists, but is worthy of trust, and perhaps even "worship" -- although if worship was one of his demands, I'd be instantly suspicious of his motives and trustworthiness and maturity.

This is what fundagelicals don't get. First you have to substantiate that any sort of god exists, then that your particular god exists, then that he has the attributes you claim he has, and has the same demands you claim he does, and that people should accommodate those demands. It's a long chain of hurdles to clear, and so often, they just give up and say with an exasperated sigh that NOTHING would serve as proof. Well it's a ridiculous truth claim presented without evidence so ... duh, yeah.

Anyway ... the reason gods are always presented as supernatural (super-natural = above, beyond, outside of the natural world) is that makes them ineffable and not subject to observation or intersubjective confirmation of any kind. The gods must always lurk in the extreme corner of your eyes, never right in front of you. Right over there in the "blink and you miss it" territory of ghosts and leprechauns.

Yeah, what's up with the invisible game? Doesn't make sense for a god who wants the whole world to know him, yet he hides himself from his creation. Great plan.
"Jesus saith unto him, Thomas, because thou hast seen me, thou hast believed: blessed are they that have not seen, and yet have believed." -John 20:29