Some of you in this thread need to remember an old saying about not fixing what isn't broken.
Of course, by your reasoning it IS broken, so I doubt I'm going to get anywhere with that.
So the current marking rule gives players a choice of playing at the front of their thrown disc by using a mini or behind it by using the thrown disc. Big deal. That gives them just two available options 8 1/2 inches apart on the same line. I don't think that's going to make the Large Hadron Collider to eat a hole in the earth. There's nothing wrong with giving players an option.
Some folks, believe it or not, think the marking rule should be liberalized even further, where a player could place the mini at any point along the thrown disc. Front, back, left side, right side, wouldn't matter. Boy would that make things "inconsistent".