The following equations will help to understand what article is, as well as will help to destroy the myth that definite article is obligatory before superlative degree of comparison, ordinal numbers, next, last, etc.
one of the most = a most "..."A most brutal murder," said he...". Anna Katharine Green, A Strange Disappearance, 1880 one of the next = a next "...a next day the bell rings...". Lore Segal, Lucinella, 1976 one of the last = a last "...He gave him a last look...". Adolph Francis Alphonse Bandelier, The Delight Makers, 1890 one of the only = an only "...an only child to decent parents of no irregular point of view...". Richard Ford, The Sportswriter, 1986 one of the main = a main "...They failed to get a right of way over a main highway...". Edward H. Hempel, Small Plant Management, 1950 one of the first = a first "...That film was a first cause which led eventually to Craig...". Samuel Nathaniel Behrman, But for Whom Charlie, 1964 one of the following = a following "...no driver of a following car would suspect that I was not a Han like himself...". Philip Francis Nowlan, The Airlords of Han, 1929 one of the best = a best "...and it was a best seller from the very start...". Frederic A. Birmingham, "The Infinite Riches of Ben Franklin", 1982
Top answer
Well, your first one at least is a bogus reference: it is an example of a different definition for 'most' as adverb— 'very': 2. Very: a most impressive piece of writing. I haven't bothered to go through your other examples.
— Mister Micawber
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'Most' is always adverb when you use it to form superlative degrees of comparison. There's no bogus. Bogus is to start regarding 'most' something different once you change its article.