He is a little more sophisticated man.<<Complete sentence
It is ungrammatical to say "He is a little more sophisticated man" OR "He is a little more smart and sophisticated man". My reasoning as to why is as follows:
The problem is that 'a little' is a construction in itself. 'Move over a little'. 'Move over a little more'. Whatever you analyse 'little' as here, it isn't a noun. Realistically, it is probably a contraction or ellipsis of 'a little bit'. Either way, if you say 'a little more', the 'a' is part of the construction, it is not the indefinite article to a noun. In 'a little more sophisticated movie', the 'a' belongs to 'a little', not 'movie'. So we are short of an indefinite article. If we say 'an a little more sophisticated movie', that too is wrong. The solution? Don't use 'a little', use 'somewhat' or 'slightly' or some other construction that doesn't already use 'a'. 'somewhat more sophisticated', 'slightly more sophisticated', 'a little more sophisticated'. Only 'a little' requires 'a'. Oh, and if you say 'it is little more sophisticated (than)', that means 'it is NOT MORE sophisticated (than)' which is an entirely different meaning. 'It is little more sophisticated than the technology of last century."
http://dictionary.cambridge.org/grammar/british-grammar/little-a-little-few-a-few
In the same way, if you say "He is an 'a' grade student", 'a' is not an article, so you need 'an' as the indefinite article.
Does anyone have a different viewpoint as to why "He is a little more sophisticated man" as a stand alone sentence (not followed by 'than' or any implied content) is ungrammatical?
Solution 1:
Your assumption (or argument) lacks one important principle in understanding how the English language works. English like any other languages in the world doesn't work like mathematics.
You are claiming that "a little more sophisticated man" can't be used because the "a" belongs to a set phrase a little and the "a" can't modify the noun man. You concluded that "an a little more sophisticated man" is wrong.
Now, contrast the following sentences using the same logic.
This is a problem.
This is a bigger problem.
This is a little bigger problem. (The Google search shows 16,200 hits)
This is a slightly bigger problem. (The Google search shows 10,600 hits)
The noun problem is a countable noun. Therefore, No. 3 should never be used because, I quote the reason you provided, "The problem is that 'a little' is a construction in itself."
How can we possibly explain why No. 3 works? We can only explain that it works because the adverb little is synonymous with slightly. Otherwise, No. 4 or "This is an a little bigger problem" should be used. But I have never seen "I have an a little bigger problem" in my whole life. English never allows two articles to be used consecutively.
Does No. 3 read like @curious-proofreader commented?
A little bigger problem = A little problem which is bigger.
No, it doesn't.
I agree that in some context, using "slightly" could sound more idiomatic, but in other context, especially when "a little" is placed before comparatives such as "more complex", "more complicated" and "more sophisticated", etc. using "a little" doesn't sound unidiomatic at all.
This is not a grammatical issue. If it is, No. 3 above should never be used.