First, not only does the Book of Mormon now have wording in it that reflects a view of the Godhead more in common with traditional Christianity than modern LDS theology, it was edited in the 1837 edition to remove the most difficult examples of this, like this one -
1 Nephi 13:40
1830 edition - "... These last records ... shall make known to all kindreds, tongues, and people, that the Lamb of God is the Eternal Father and the Savior ... "
Current reading - "... These last records ... shall make known to all kindreds, tongues, and people, that the Lamb of God is the Son of the Eternal Father, and the Savior ..."
I'm not sure how Joseph Smith's changing view can explain this away without suggesting Joseph Smith had a heavier hand in providing the material of the Book of Mormon than is usually assumed. At least, assumed by the non-critic.
Also, consider this -
History of the Church, Vol. 1 - the account of the three witnesses receiving their witness of the plates -
pg. 54, end of page -
"Not many days after the above commandment was given, we four, viz., Martin Harris, David Whitmer, Oliver Cowdery and myself, agreed to retire into the woods, and try to obtain, by fervent and humble prayer, the fulfilment of the promises given in the above revelation--that they should have a view of the plates. We accordingly made choice of a piece of woods convenient to Mr. Whitmer's house, to which we retired, and having knelt down, we began to pray in much faith to Almighty God to bestow upon us a realization of these promises.
According to previous arrangement, I commenced prayer to our Heavenly Father, and was followed by each of the others in succession. We did not at the first trial, however, obtain any answer or manifestation of divine favor in our behalf. We again observed the same order of prayer, each calling on and praying fervently to God in rotation, but with the same result as before.
Upon this, our second failure, Martin Harris proposed that he should withdraw himself from us, believing, as he expressed himself, that his presence was the cause of our not obtaining what we wished for. He accordingly withdrew from us, and we knelt down again, and had not been many minutes engaged in prayer, when presently we beheld a light above us in the air, of exceeding brightness; and behold, an angel stood before us. In his hands he held the plates which we had been praying for these to have a view of. He turned over the leaves one by one, so that we could see them, and discern the engravings thereon distinctly. He then addressed himself to David Whitmer and said, "David, blessed is the Lord, and he that keeps His commandments;"(4) when, immediately afterwards, we heard a voice from out of the bright light above us, saying,
p.55
"These plates have been revealed by the power of God, and they have been translated by the power of God. The translation of them which you have seen is correct, and I command you to bear record of what you now see and hear." (my emphasis)