In this tutorial, we'll take a bunch of generic "cowboy/campfire" open chords and discuss what specific tones you can add to them to transform them from their "bland" state into something more "modern-sounding" and evocative.
These voicings will then be expanded upon by putting them into context, grouping each of the chords with upper-register common tones to produce that "upper-register sheen" you may recognize from favorite singer-songwriters, indie-rock artists, and so on.
We'll then work them up with different pick-style (Dave Matthews, Neil Young, and more) and fingerstyle (Elliott Smith, Extreme's Nuno Bettencourt, piano-style moves, etc.) options. We'll conclude by putting all the concepts together into a common pop/rock progression - as if you're using these new techniques to personalize chord progressions in one of your own songs.