First let me say that this kind of writing must come from an understanding of traditional jazz voice leading. I say this because it is essentially an "ears first" approach to adding harmony to a standard and the danger is for it to sound so arbitrary that the original tune is completely lost. It is difficult to replace tonal chord progressions with chromatic or modal harmony without an ingrained sense of the "purpose" or "direction" of the original tonal harmony. By this I mean that a cadence such as II-V7-I has a purpose in that it leads the harmony in a specific direction. In replacing the original tonal harmony I believe that one needs to try to keep the feeling of the original harmony (here "feeling" is pretty broad and probably entails an infinite number of possibilities). If the arrangement is so far flung from the original tune that one can't get the sense that the arranger is "playing" with that tune, (stretching it, morphing it, playing with our expectations) then it begs the question why arrange this tune? Why not just compose something new?
One rule of thumb is to keep the melody intact and only change the rhythm or phrasing of it. For me this always suggests interesting directions for the harmony to take. Even if the harmony changes quite a bit as it does here I try not to over power the melody so that a sense of the original tune can still come through.
Also in this arrangement I used a common devise called a "tag". Basically that is extra bars at the end of the tune which kind of stretches it out a bit and takes it in a different direction briefly. In this case it modernizes the tune by introducing the feeling of a vamp. A tag also needs to have a natural connection to the standard so it's best to build it out of something in the body of the arrangement. I took the idea for the tag from measures 17-18 when I was working on the A section. These chords sounded like they stood on their own (they certainly stand OUT from the tune) and they quickly inspired me to build a vamp out of them. Unusual about the vamp however is the 3 bar phrases.
In addition to triads and seventh chord voicings there are also quartal voicings. Quartal refers to the interval of a 4th so that can include also the augmented 4th and diminished 5th in combination with a perfect 4th. Notice how the quartal voicings are especially interesting when the melody repeats the same note (mm 29-32) as the original melody does at the beginning of the bridge. The voices however are free to move under the melody and create some interesting dissonances which are completely chromatic and not tonal. This is often referred to as oblique motion.
Here is a version from a recording I made with 3 horns.