Personally whether it's high or low pitch, it doesn't matter or give judgement on any good or versatile effect unless it's sung in your default general key of range. Example I can sing and express on a high pitch, but singing high all the way makes the song stale. Alternatively I can sing expressively low, but I think that kinda singing suited more on trance or Mandalay stuff, because of my tone at that range.
I remember an old american idol audition where the girl sang high all the way and although she hit each note and expressed it out, the judges weren't too impressed. Simon said it was "dull".