The variant is intended to keep eliminated players engaged, add a bit more chaos and some more "take that" nastiness to the game. It runs a couple of risks though:
* Kingmaker issues: eliminated players may have too much control over who wins
You could impose a rule that states the JSDF cannot affect the same monster two actions in a row (eg. If you remove a heart benefit, then you cannot claw against the same monster.)
I would also have heart tokens removed by damage from the Tokyo monster.