Greetings Leolaia,
I appreciate your logical approach. You asked repeatedly what I believe regarding claims of extra-biblical supernatural phenomena. I am in fact a skeptic of all things, not merely the supernatural, but of governments, bereaucracies, and institutions that have a self-interest to preserve.
How does a skeptic evaluate supernatural claims without including the bias of "there is no supernatural so all things must have a natural explanation"? If my anti-supernatural bias prevents me from investigating the supernatural because I cannot admit the possibility before I even do the investigation, the research is self-defeating before it begins. Merely denying the supernatural excludes the possible outcome of finding the supernatural, so I do not do that.
Some evidences are better than others. Written evidence is usually better than oral, and documents closer to the date of an event are better than contemporary ones. Some evidences are not evidence at all: assumptions, biases, mindreading of motivations, etc. When written evidence has no concrete support or refutation it becomes subject to literary analysis whose rules vary by special interest groups based on preconceptions and biases (whether they are admitted or not). In biblical literature the literary analysis abounds and every academic finding can be and is opposed with a contradictory academic finding. In some circles deutero-canonical books are regarded as blatant frauds, in others, sacred--and each has their own literary analysis to "prove" it. From there the discussion degrades into a contest of whose literary analysis is better.
What can be done by the skeptic who does not wish to preclude the outcome of the supernatural when investigating the Bible? One approach is to apply the criterion of consistency. For example, some of the most credible Christian teachers today, Wayne Grudem is such a person, strongly believes in modern prophecy but published that the best he has seen from the best prophet in his own church is a 40% accuracy rate. That is inconsistent in the extreme. Virtually all such prophecy-minded churches that dare do so acknowledge similar rates. Their claims of religious supernatural activity may therefore be dismissed. Consistency requires, well, it requires consistency. Likewise, UFO enthusiasts have yet to produce consistent evidences of any kind to support their cause. Governments are extraordinarily inconsistent in telling the truth, so what they have to say should always be assumed to be inaccurate.
Scriptures themselves are nothing but one continuous story of supernatural revelation from one God to one human after the other. Virtually every alleged encounter between this God and a human results in this God delivering a future-telling prophecy, which the people then act upon: Abraham goes to Canaan, the patriarchs go to Egypt, Moses leads the Jews out of Egypt, temples are built, animals are sacrificed, and a Messiah is anticipated.
What I found consistent, and thus believable (in lieu of no contravening concrete evidences), is that the theme is pervasive (God is both Creator and Savior) and has revealed Himself to humanity through selected prophets. Either the story is one very long conspiracy of intentional lies from Moses to the apostle John (where at times the entire nation of Israel participates in the deception) with each and every patriarch being so evil as to add his own set of lies to further the story, including Jesus who said the whole story was true, or, the story being told is as accurate as the indviduals can make it. What is more plausible? To me, it seemed more plausible that religious minded indivduals (the majority of whom had nothing to gain by lying) did not all lie to the last man and told the truth. That kind of consistency of supernatural interaction with God is what convinced me the collected work is valid. Others will find the consistency criterion to lead them to say the whole thing is a conspiracy of false religion.
That is my personal story. Other groups, like the Mormons and the WTS lacked credibility for me because their histories did not continue the story of the Bible but created brand new recent plot lines, they claimed prophecies that contradicted the very Bible they claimed to follow, and their future-telling prophecies failed to always come true.
Yes, I am a skeptic of all things. But I do not let my skepticism rule me. For me, the story of the Bible demanded my faith to be placed in Christ. Faith, the very definition of faith, is believing in what cannot be seen or proven, for if it could be seen and proven then faith would not be needed.