Thank you for playing the game. Admittedly, this nitpick of the icons at the center is caused by a lack of time. I wanted to implement that sort of powerup, but time constraints stopped me from going further. This sort of thing is up for consideration in the future, so I appreciate your point.
So its mostly placed there to display the party members in the game and to prevent empty space in the center. But I can see how you would misled it for powerup effect buttons.
Once again, much obliged for your input on the matter.