Want to know the Top 10? Go look at the tier list.
But which character is best isn't a good indicator to how much potential a player has regardless of the character he/she uses. If anything, rating characters just shows who is equipped for the greatest amount of conditions possible in a brawl. It's up to the player to be able to utilize the right moves at the right time, so more often than not, it's down to the intelligence of the player.