Well well well sir! You seem to have figured it all out huh?! BUT I CAN TELL YOU THAT YOU ARE WRONG!
A FF is not just something you "throw around". NO. It comes from within, from outside, from the universe it self! You will need not only personal powers to master a FF while being a IDS but also a thousand seagul souls to prevent the worst outcome of casting a FF - the ultimate death of a billion BMS (blinking master scales)!
If you manage to contain the powers of a thouasand seagulsouls then you may cast a FF towards your own face! but only if the gods thinks you worthy of doing so!