During the command block fight, the command block could gain direct control of withered mobs, causing the mob to emit command block particles, and making it significantly stronger. For balancing purposes, I think this feature should only be enabled when the wither storm was spawned with a wither storm beacon.

I just realized now, that’s literally the lore behind the withered symbiont

I personally don't feel the command block should take direct control over the withered mobs, as mentioned this is effectively what has been done with the Withered Symbiont