Idea for Rek'Sai bite

The current rek'sai e, while unburrowed, is slightly useless due to people building him full tank and is kinda boring. It makes the champion boring to me. My idea of a rework is that it should function slightly like a volibear bite, except suited more for rek'sai. Here's what I think Original: Furious Bite RANGE: 250 COOLDOWN: 12 Furious Bite UNBURROWED - ACTIVE: Rek'Sai bites her target, dealing physical damage that is increased by 1% for every 1% of her current Fury. If Rek'Sai has full Fury, Furious Bite will deal true damage instead. MINIMUM PHYSICAL DAMAGE: 80 / 90 / 100 / 110 / 120% AD MAXIMUM/TRUE DAMAGE: 160 / 180 / 200 / 220 / 240% AD Reworked: Furious Bite RANGE: 250 COOLDOWN: 12 Furious Bite UNBURROWED - ACTIVE: After gaining full fury(spell is only able to be casted after having your fury bar filled), Rek'Sai is able to bite her target, dealing true damage based on their missing health. TRUE DAMAGE: 8 / 9 / 10/ 11 / 12% of target's missing health(if this is too op, it can be targets maximum health or rek'sai's max health I think this will add more features to rek'sai and more than just one use for the fury. I think rek'sai as of now is way to straight forward(maybe that's just me), but tell me what you think.