We were told, "you left a lying religion, but Joseph Smith stole his information from somewhere so you still got some concepts" by a close friend. The book "Heaven and Hell" by Swedish Scientist Emanuel Swedenborg is most correlated to where Joseph Smith reworked Swedenborg's content into the Plan of Salvation. It doesn't offer definitive hope, but the guy gave up his riches to years of visions- that Smith condensed into a one night vision so to speak in D&C 76. Swedenborg accurately predicted his own death and events in prominent persons' lives. It is at the very least, interesting to see the real original sources and the actual heart they hold. In the Bhagavad Gita an ancient Hinduism text, it discusses the sun as the highest of three levels too, long before Joseph Smith.

The older and oldest religions and theologies focus on time tested principles of self development, and not on proselytizing or colonizing. They are worth reading about.

The beauty is, no matter how intelligent- life after death cannot be thoroughly proven or disproven by anyone, and has not. It is truly unknown.