Choosing music for your ringtone is delicate, because you express yourself whenever it plays in public. I use "Afternoon Chill" and "Well-balanced" on my phone now and loved "Ambient Mood", "Moonlit Haze", "Illumination", etc. on my old RAZR - ringtones that instantly set a mood without being too intrusive. Something to wake up to and go out to.
Also, if your phone plays MIDI ringtones, you might want to try using the original MIDI file.