Thoughts on Health Drain mechanic to rework Spell Vamp

I'm start thinking ones I read the description of Hunter's Talisman:

UNIQUE – TOOTH: Damaging a monster applies HEALTH DRAIN, which deals 25 magic damage over 5 seconds while restoring as much as health.

So what if spell vamp could function like this:

• Spell vamp is a defensive stat which deals an amount of damage over 5 seconds while restoring as much as health when damaging with either champion abilities. It only works for active champion abilities that do not modify basic attacks or apply on-hit effects (including true damage abilities).

This means spell vamp is now a flat number rather than an percentage.

#Items

• : Now gains 10 spellvamp Tribute doesn't deal damage anymore So that's about 10 damage dealed & 10 damage healed after 5 seconds
• : Now gains 15 spellvamp Tribute doesn't deal damage anymore So that's about 15 damage dealed & 15 damage healed after 5 seconds
• : Now gives 30 spell vamp
• : Now gives 40 spell vamp
• : Is now an unique passive similar what they did with

The healing scales with bonusses like

Thoughts?