The last section is one of the beautiful things I ever heard.
I love the banjo and claps during section two, and the intimate romantic strings in section three. The saxophone sounds so real.
The mix is clean most of the time, and the reverb and delay effects contribute to a rich romantic atmosphere.
I really like the choice of chords thorough the composition.
The strings stand out as not being humanized, and the violins mask some countermelodies in section two - perhaps piccolo or flute+piccolo in octaves could be better for those counter melodies.
To humanize the violins in section two, and in general, try to "ease in" each melodic phrase with dynamic and expression automation, and add an "ease out" by decreasing the dynamics and expression at the end. It's like creating an arc but with a long flat top. You can also change the note timings slightly so that they're not perfectly on the beat.