They do believe in a virgin birth, they think the father and the son are 2 separate entities, and that satan is a fallen angel while christ remained loyal to his father, they believe we are all children of God and in no way downplay his holiness, if anything they elevate it, they in no way shape or form believe Joseph Smith was greater than (or equal to) Jesus (this was one of the blatant hyperbolic misrepresentations that really jumped out from this video), to my recollection, they do not believe Jesus had earthly wives or children, the "god was a random lovechild" is more hyperbole from the video, they believe that in salvation and through the sanctity and bonds of marriage (and potentially of a family) can last for eternity (if you followed the teachings of christ while you are here on earth), yes.. consistent with what you say is in the bible in the afterlife they believe we are all spirit beings, and the afterlife is without sex, there is no need for it, salvation is glorious enough in and of itself, besides sex is a bodily function, just as you say is mentioned in the bible. It is very much based on the bible and biblical teachings, it just adds a few extra layers above and beyond the typical biblical teachings.
The video is propaganda and you are taking it at face value.
As I said the video takes basic tenants and expands on them and misrepresents things quite a bit, it was propaganda based on kernels of truth, and goes out of its way to portray them as cultist and not based on the bible at all, when in fact their religion is first and foremost rooted in biblical teachings and study, and their interpretations and beliefs regarding the bible are essentially the same as any other christian religion. Tales of the flood in Sunday School, Garden of Gethsemane, sermon on the mount, Daniel and the Lion, all the normal christian teachings and tenants are there.. and consistent with the bible, they do not reinterpret it, they just expand on the tale with another volume.
I can't believe I am defending Mormons, but I was raised in a Mormon family (before I got old enough to reject it - ~13 years old I started seriously doubting- I was steeped in their doctrine) and am familiar with what they believe - as crazy and implausible as I consider Mormon beliefs to be - their biblical teachings are in line with other christian faiths, and the portrayal of their beliefs that go above and beyond biblical teachings are presented in this video dishonestly, and it appears deliberately to make them look absolutely bat **** crazy and not in line with Christianity, when this is not really the case (the not in line with Christianity part), they are most certainly Christian.. very much so.