Would be cool, but it can't really be done.
Player type collision boxes are created through the script. And the default player's collision is the same length and width.
Here is a visual representation of a default player, with the darker square outlining the collision box:

It is possible to shorten the length of the collision box, to create a rectangle shape, instead of a square one. Like this:

That would work just fine up until the player decides they want to turn. Then what will happen is this:
