But we are comparing apples to oranges here:
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Knockdown can always be resisted reliably at the cost of half a move action and thus might be a small hindrance at best to some while having near to no impact on others.
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Enrage (or however you want to name your bane) is resisted as a minor action (good choice) but with a chance failing, which can lead to some characters being taken out of combat completely (pacifists, boon-focused, and insubstantial characters)
So the difference in variance and the potential upside is massive, so I don’t think that comparison is all that helpful.
But you could easily throw yourself onto the ground to become a smaller target vs. ranged attacks, giving you the same effects as Knockdown. This can’t be done as easily with your infuriate, mechanically and narratively, as it would probably require a boon counterpart to emulate that effect.