Circle Of Fifths Progression Analysis

How significant are circle-of-fifths progressions and minor chords and minor keys, in the two movements that you have studied? Throughout the 1st and 3rd movement of the Symphony, Mozart implements a circle-of-fifths chord progression on several occasions. The first instance of this in the first movement is from Bar 31 to Bar 34, where on the first two beats of every bar there is a descending pattern of diminished chord, and on the second two beats there is the circle-of-fifths pattern: A7 / D7 / G7 / C7. Bar 35 ends the progression with an F Major chord.
From Bars 139 - 145, we are given another circle-of-fifths progression. This progression interchanges in tonality - a minor 7th chord, followed by a major 7th chord, and so on. Every half of a bar is a falling two beat-sequence; however each sequence fits into the tetrads. From Bar 143, the progressions become more frequent (two a bar). From Bars 148 - 153, we are given another circle-of-fifths progression - however, this progression is not based on chords, but on the key. Each key (with the exception of the first) spans two bars, yet irregularly - the modulations are implemented in the middle of the bars (the third beat).
Every two bars follow the pattern of:
a) Major 7th chord in the 3rd inversion
b) Major triad in the first beat, minor in the second, diminished in the fourth; all in first inversion; the bass note is absent on the third