Bleach: Hollow Flash

Well shinigami don't seem to get much and they have a awesome feature that lets them lose control and rampage a bit. My first suggestion is: When a substitute shinigami losing control and goes on a rampage do to having a natural regeneration of health why not make it so it happens until you reach up to about 30-40% your health that way it last longer than about 2 seconds. Would be nice if sub shini had a bit more to them than just a zanpakuto and possible Vaizard. If they could have maybe a earthly teams they could join to give them boosts to maybe training or something.