[Poppy] There is simple way to make her playable

After play more poppy then any person would care to admit i reaize there are some flaws with her as a champion the biggest one I notice is the fact that her q Devastating BlowCOOLDOWN: 8 / 7 / 6 / 5 / 4COST: 55 MANA Devastating Blow ACTIVE: Poppy's next basic attack is converted to deal magic damage and deals bonus damage equal to a flat amount plus 8% of the target's maximum health. Devastating Blow's percent health component cannot exceed a damage threshold. TOTAL MAGIC DAMAGE: 20 / 40 / 60 / 80 / 100 (+ 100% AD) (+ 60% AP) (+ 8% of target's maximum health) MAXIMUM BONUS DAMAGE: 75 / 150 / 225 / 300 / 375 There are many champions in league of legends that have percentage based health attacks (suck as vayne) there also 3 champions (vigar nasus and sion) that scale endlessly, even elise has a simalar attack and the one thing poppy is stuck with that none of these champions are is the fact that there is a cap to how much damage. With the meta going in to shift from assassins tanks this leave an opportunity for poppy to make some sorta impact if this skill was fixed correctly. my idea is to lower the percentage based health done on champions to about 4% and remove the cap but on the same note it should refund a percentage of damaged dealt back to poppy's hp fixing her other built in problem of no sustain If anyone has any other ideas or just wants to tell me im wrong i would love to hear some feedback