Watch the Embellished Melody online guitar lesson by John Stowell from Modern Chord Melody
For the embellished melody, I'm adding some new rhythmic information in terms of some simple fills; these are sometimes modified arpeggios derived from the chord shapes used in the melody. I'm also trying to make more of a contrast between the rubato sections of the melody and the phrases where time is implied for several bars.
It's interesting for me to hear multiple recordings of the same tune over a period of a few years to observe the evolution of a piece as phrases and embellishments change and evolve. I don't have a blueprint for how a composition should change over time; I know that a piece will remain interesting and engaging for me to perform again and again if I give myself permission to re-interpret the melody as well as the improvisation. Look to other musicians for inspiration and guidance as to how to accomplish these goals in your own writing and playing. Don't be afraid to copy in the beginning; your own style of improvising and composing will emerge over time. Recording your own work is crucial to your development. Documentation gives you the ability to step back, evaluate and react in a more objective way that isn't possible to do while you're hearing yourself as you play.