When I need some harmonic freshness, new chords with original functions and crazy guitar voicing, the first thing that comes to my mind is: “Let’s transcribe some Guinga stuff.” Guinga is a genius composer of Brazilian music and a very original guitar player, with a very personal approach of the harmonic aspect of the instrument.
Here a transcription of his guitar part on Valsinha, a composition by Vinicius de Moraes & Chico Buarque, where he is comping Brazilian singer Leila Pinheiro in a duo setting.
The whole thing is in 3/4 but with a rubato feel. Some chords are also arpeggiated. Listen to the recording.
I will do a music theory post to analyze the way Guinga approaches and rearmonizes the song.