Mixing up TW is cool, but "lol you can't use a bunch of dudes" isn't much of a concept.
The temporary buffs to Mace and CUP were cool because they made lousy characters useful, and made teams viable that otherwise wouldn't be.
This just hamstrings everyone. That's not fun, it's just changing things for the sake of changing things. Also, just because a thing "involves the community" doesn't automatically make it cool and engaging. You're basically asking people to choose which of the characters they invested time and resources in they want to throw out the window for the duration of the event.
EA Staff