Some of my favourites haven't got or had great voices but just great songs.I really think that the right voice singing the right song is far better than the best voice in the world singing the wrong song.
Singers like Celine Dion, Mariah Carey and the late Whitney Houston are considered to have brilliant voices but I find them a bit too much. I listen out more for the tune than the voice.
Freddie Mercury voice wasn't brilliant but he was the ultimate showman and sand the right songs. I loved his voice.