Frenzied enchantment rework idea

I think a better change for Frenzied enchantment would be:

While you are at less than half health, your attack speed and movement speed is increased for 30 seconds.

Level 1: 10% attack speed and movement speed
Level 2: 20% attack speed and movement speed
Level 3: 30% attack speed and movement speed

So this triggers when you are at half health and since its on for 30 seconds, you will still keep the effect after you have been healed!

It could also be changed to a Powerful enchantment category costing more.