It can't be much simpler than gstreamer. The whole gstreamer code in Panucci is one file in 129 lines. I cleaned up the backend a while ago and it is modular so it's easy to add support for more media frameworks if you want. Only gstreamer is supported now though and I don't plan on adding more myself, at least not right now.
import QtMultimediaKit 1.0 Audio { source: '/path/to/file.mp3' playing: true }