You put "more natural" in quotes, indicating that the picture you've used is meant to illustrate how the characters actually don't stand in a more natural way in the game. However, the picture you've used has six characters standing in a triangle, which is effectively a way that is not typical of how the characters stand around in an actual game with four characters, without any modding.
It's literally the game's DEFAULT formation. It's just its version with two extra slots filled. Otherwise it's a rhombic shape. Remove Shadowheart and Lei'zel and you have what you are playing with.
I concede that the picture of that thing that was modded to have more characters looks bad because of the positioning of that many characters together.
