Just like some people enjoy playing fantasy football game, I play fantasy music game in my mind. Especially when I listen to the voice I really like. I go through my music library and imagine what the song will sound like if she or he sings this song, and find the best match. Just like selecting the covers album playlist for them.
People's voice is many-sided, but I think it really shines when the right song (or text) is given to it. The right song; the song which emphasize the appeal and personality of the voice. Deft producers/composers know the best voice range of vocalists, and make the song which brings out their best. (And most cases, vocalists later want to try something outside of their zones and leave the producers and go haywire... sad, but that's how things go.)
Having said that, the best appeal of the vocalist can be varied according to the listeners: Some people adore his base voice and consider it as his best weapon while others adore his falsetto. And what I do is a fantasy selection which completely based on my likings. It's all fun. I imagine how the songs like, and alter the tempo or version if necessary. And when I found the perfect match, I smug in and resist the urge to write a suggestion mail to that vocalist..
Yellow Butterfly - Tahiti 80
Xavier Boyer is one of my favorite vocalists. Love his light foggy voice. Wishing he will sing more standards in acoustic version. (And I found a Japanese musician, mabanua has very similar voice type but denser. It's also fun to discover similarities in voices..)