JOEL - The most widley used and accepted English version of the Bible is the King James version. The Book of Mormon was written in a similar style so as to be be more easily understood and compared to the King James Bible reading people of the latter-days.
The Bible was written in Hebrew, Aramic and Greek, but none of the original manuscripts exist today. Even though they were copied and translated into many different languages, the process of copying and translating could introduce errors and mistranslations. The problem with looking at the original Hebrew or Greek is that no two people can completely agree on what the translation of the words should be.
Similarly, translating the Book of Mormon into the "vernacular English" would also not be easy since we don't have the original gold plates to work from. Also, not everyone would agree on a correct translation from the existing King James style version into vernacular English. I suppose the Prophet or Apostles could do it, but they don't really have the time to take on such a task, which is probably not really needed anyway. For the last 172 years they have been telling us what those scriptures mean and how to apply them in our lives if we take the time to do the research. If you are interested there is a book called "Reading the Book of Mormon in Plain English." written by Timothy Wilson. It is one man's attempt at writing the Book of Mormon into plainer more modern English. You can read about it at this site: http://www.aml-online.org/reviews/b/B199854.html.