@Meddler You can easily adjust Poppy's stats to be healthy instead of scrapping her entire kit.
Unlike other drastic reworks, her kit isn't actually that bad on a fundamental level yet Riot has said they want to only keep her E and make her into a Tank. I really don't understand why they want to completely kill a character.
It would be like changing Olaf to only have his Q.
It's the random things on her kit that are bad. She has the ability to ignore almost all damage while also getting incredibly high Armor and AD naturally + high base AD and Armor.
Give her Jax's base Mana, Mana Regen and Armor. Also give her Scaling MR per level. The rest of her stats can stay the same.
Passive should be some sort of Shield mechanic to give her incentives to rush forward like her current Passive does without being an obscene amount of damage reduction. Potentially giving her a shield whenever she takes damage, the opposite of how Vi's shield works.
Q should be a more straightforward Physical damage ability instead of being almost 400 damage that converts the entirety of an Auto to Magic. Would be nice if it Cleaved instead of just being single target.
W stacks should give MS instead of Armor and AD, with the Active giving full stacks + an additional amount. Potentially lost while on CD to make her boost feel like it has impact. Make the stacks only generate from instances of damage taken instead of just being in combat, to give her incentives to just run up and start brute force killing people.
E deals Physical + Bonus AD and AP and applies on hit effects as an autoattack. The damage is doubled if she collides with a wall with her target instead of dealing base magic + AP then getting an obscene amount of magic + AP damage when colliding with a Wall. Deals moderate damage instead of super high burst.
R: For 6 seconds and 180/130/80 CD, Poppy deals 10/30/50% more auto related damage to her Target and takes 10/30/50% Less Damage and CC from all Other Targets. She is no longer straight up immune to everyone else, so she keeps the high speed dueling elimination without completely being able to ignore the entirety of the target's team.
Her kit is incredibly iconic and she occupies a space of Initiation Fighter Assassin that nobody else fills. She is like Vi + Jax, and it is honestly too interesting to just remove completely.
Don't just make her into another Tank initiator like Sion, please Riot. She is Fighter/Tank, since Fighter/Assassin doesn't work for her, and needs to stay like that.