What we can't do is add extra options/icons to the left of the Save/Disk symbol for example. The obvious one would be a background music on/off icon.
This isn't an issue for me, as adding music was not a primary concern... But I'd be interested to hear any alternatives as to where you'd put something like that, Sophia?
* A 0.1KG Remote Control artifact when wielded could do the same thing

* Replacing a character's Punch ability with Guard (as we can have multiple parties in DSB)
* INSERT YOUR IDEA HERE...