Removing the ability to have empty equipment slots

[The Data Mage]

Hey. Im looking into the possibility that all party members must have all of their equipment slots filled at all times.

What this entales:

When equiped equipment is selected and attempted to be unequipped, unless it is swapped with another piece of useable equipment, it wont unequip...

IE, sword is equipped, if you try and swap it with nothing (unequip) nothing happens, but swap it with knife and it would allow it.

Make sense?