Joseph Smith's vision was not in itself a unique experience in the 19th century, what legitimized him as a prophet was the book of mormon. In the concluding paragraphs of the book of mormon, it states: (also known as moroni's challenge) 4 And when ye shall receive these things, I would exhort you that ye would ask God, the Eternal Father, in the name of Christ, if these things are not true; and if ye shall ask with a sincere heart, with real intent, having faith in Christ, he will manifest the truth of it unto you, by the power of the Holy Ghost.
5 And by the power of the Holy Ghost ye may know the truth of all things.(Moroni 10:4-5)
I have read the book of mormon and prayed to know if it is true and I have received my answer. I realize that many may struggle with this approach to understanding truth as we are all endowed with the scientific world view. A quote from a good friend of mine (who wrote a fascination anti-mormon book featuring this quote) sums it up really nicely "I'm afraid that the river between us is still unbridged and perhaps unbridgeable- the reason for that, as I see it, is essentially epistomological, I accept spiritual revelation as a valid way of knowing and you do not"
Also, he is not perceived to have god-like powers in mormonism. Jesus Christ is viewed to have these powers but Joseph Smith is seen as an instrument in God's hands. He is very much a human but was the mouth piece for God in our day. “It is my duty to say to you that the
need was never greater [for] new revelation than now.” “The doctrine of
inspiration is lost. … Miracles, prophecy, … the holy life, exist as ancient
history [only]. … Men have come to speak of … revelation as somewhat long ago
given and done, as if God were dead. … It is the office of a true teacher,” he
warned, “to show us that God is, not was; that He speaketh, not spake.” –Ralph
Waldo Emerson
Joseph Smith has no say in who gets into heaven or not. God is our ultimate judge and Jesus Christ is our mediator who has atoned for our sins so that we may make it back to our Heavenly Father. I certainly cannot "prove" it to you in any way, it requires personal effort. I have some interesting evidences I could provide you with but I dont have room in this post.
- "Why do Mormons allow themselves to perpetuate the stereotype of having seemingly cultish communities?"
I am unsure what you mean, I wasn't aware we perpetuate having cultish communities. Our temple ceremonies are "secret" only in that they are very private because we hold them so sacred. For everything else, we do missionary work like none other and invite all to learn more about us. And we're pretty normal for the most part. I guess if you could un-pack cultish communities I could better clarify this!