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.
Following on from Kevin's 'no move bounce back request', please would you consider conditional moves. For example, in Five Line, your opponent may have to stop a four and you could say 'If (the square where he needs to put his piece), then ...' I appreciate that this would be horribly difficult but it would speed up games enormously.