Do you miss something on BrainKing.com and would you like to see it here? Post your request into this board! If there is a more specific board for the request, (i.e. game rule changes etc) then it should be posted and discussed on that specific board.
mctrivia: I consider 10% too much! Who'd play when the operator gets half? And what's wrong with playing games on this site you're proposing that aren't pure skill, such as Dark Chess or Backgammon?