The writers of the Bible were certainly not ignorant or unconcerned about Moses and Elijah and Enoch being in heaven. That is why they recorded them in scripture for us. I have cited the relevant scriptures for that. Moreover, the writers of scripture found the ascension of Jesus Christ into heaven so marvelous that they recorded that event, as well. Unfortunately, for Catholic apologists, no such event is recorded for Mary.
I am not speculating at all about the fact that Moses and Elijah appeared with Jesus Christ on the Mount of Transfiguration. We know that Elijah had been taken directly into heaven and, thus, had to come from heaven to meet with Jesus. With Moses it is not as definite, but we know that Moses must have been somewhere else before he came to meet with Jesus. There are two options - heaven or Sheol. It peculiar, to say the least, that the God who cared for Moses on Mount Nebo when Moses died decided to send Moses to Sheol. Likewise, Abraham, whose death and burial in Machpelah are distinctly recorded, is stated by Jesus as being in heaven when Jesus related the store of the rich man and Lazarus where Lazarus was resting in the bosom of Abraham and the rich man was in torment in hell.
The Mother of God is not depicted, as such, in the Revelation of John. Not to mention, how she got there bodily. There is not the slightest whiff in the New Testament about the ascension of Mary into heaven, nor, for that matter, until centuries later do we have any writings to that effect.