The immaculate conception refers to a person born without original sin. As Joseph did not give birth to Jesus, I doubt this would have been needed. A virgin-this view does seem to closely fit the Catholic one. The Eastern Orthodox churches seem to believe he had been married before and was a widow- we certainly do not subscribe to this view- officially, nor do i personally.
Assumed into heaven body and soul- Sounds like Enoch, Elijah, Mary. This is possible, but if this possible privilege were important to our own salvations, surely - would we not have heard of it in private revelation, as with the immaculate conception suggestion?
I think the answer to all of these is the answer Jesus gave about Saint John- meaning exactly what he said, as the gospel shows- “if… what is it to you?” The people misinterpreted it by attempting to find meaning in it, when Jesus had not revealed it. The silence of God is noise. Based on this- I would assume that Joseph died a virgin, especially as he is not mentioned after Jesus’ childhood, and as his wife, whom I assume was his first wife, died a virgin, and as Joseph, we are told, was a righteous man. Did Joseph ever sin-- I would say in all likelihood yet, was he born of immaculate conception, I would say in all likelihood no- why? Because we especially associate these both with Mary. Why would God exhault her so high with these, if unimportant. Joseph in contrast is not associated with either of these. Would it not be unjust if God were to honour Mary more than Joseph to such a degree, if both were as blessed and righteous?
And So, I would say that Joseph was a virgin until death, but likely sometimes sinned, and was not conceived of an immaculate conception- would we not be told if he had been?
As for assumed into heaven body and soul- this is possible of him, it could have happened. Even so- when God is silent, it is for a reason, an I would not concern myself with this hypothesis, unless I was given reason to believe otherwise. As it is, on most of these matters, all we can do is speculate!