Persichetti Exercise 3 - 51 for String Quartet

I am reviewing Vincent Persichetti's "20th Century Harmony" and just finished chapter 3!  And so I decided to do the first exercise that looked good to me to try to make an actual piece of music out of (I don't like exercises for their own sake - I think I should always be trying to make living, breathing music).  Here is the prompt for the exercise:  "12.  Harmonize the following melody in four string parts using dominant seventh chords exclusively.  Much contrary and oblique motion and several inversions should be used."

Like I said, I tried to make an actual piece of music out of it and not be too much of a stickler to the rules.  I also tried to approach it not like a chorale exercise - let me know if I've succeeded on that front!  Thanks for listening and I would appreciate any suggestions, critiques, comments or just observations!

It sounds very good, very musical and coherent.