Here are some neat voicings I picked up from listening to some live recordings of Sébastien Giniaux that could add a bit of flavor to your playing. They work especially well for comping long notes on top of a steady rhythm player. 

Take the first 4 bars to the ballad “Claire De Lune” as an example:

| D- D7 | G-     | C7     | F     |

You probably have a way to voice that already, but now try these alternatives (Note: the number in the upper left corner of each fretboard image indicates the starting fret)

Those Dominant 7 chords and the G Minor and F Major are a bit different, right? 

Theory-wise, these are simple major/minor/dominant chord inversions, but jumbled around in that way they have a more ethereal quality to them, giving the chordal movement a somewhat  ”classical” feel. 

To apply them to other songs, think of positioning yourself relative to the root note you already know. For the major/minor chords with roots on the 6th string just slide up 3 frets (minor) or 4 frets (major) to the 3rd and start the chord voicing pictured. For a dominant chord with a root on the 5th string, hop down to the dominant 7th on the 6th string 4 frets up.