Football would be better as far as analogies go, but I think the point of the baseball scale is that is it a scale. Baseball you got four steps, with sex you basically have four steps as well, kissing, groping, licking/sucking, intercourse. If you are going to go the football route then you have to figure out 96 more things to through in there (in order to get from endzone to endzone, and how would one handle a bad punt
). I guess you could use anal for one, maybe bondage.. but I would be hard pressed to find many more than that, well many more than that that enough people do to warrant a change in game!!