I've been brewing this for a while, and it boils down to her W as a whole, her R because it's lackluster, and her E for it's unreliability. I'd also like to see her passive worked on a bit, too. Make it more about sustain first, and poke second, and fun for the poking. I'm aware I may be overloading her, but it just looks like so much fun after figuring out the kit's functionality.
PASSIVE - _Hero's Resolve_ - Every 14/10/8 (Level 1/7/13, after thrown or broken) seconds, **Poppy** gains a **shield** equal to 10% of her **maximum** hp (+10% of **current** hp), refreshing the duration of any other shield she has. If _Hero's Resolve's_ shield takes damage, it is refreshed after 5 seconds if not being damaged by champions or monsters.
_Shield Throw_ - while **shielded** by any means of at least 50, **Poppy** gains 350 attack range and her basic attack timer is reset. She throws her buckler (projectile) removing her **shield** and her basic attack deals 50% of the **shield's** total value as magic damage. The buckler will bounce in a 60 degree cone away from the nearest wall, tending toward **Poppy**. If the **shield** was less than 100, it shatters on-hit, dealing it's full value. When a fallen buckler picked up or caught within the next 3 seconds, she gains _Dented Shield_, shielding herself for 50% of the original shield's value for 2 seconds.
When Poppy is shielded by any means, _Hero's Resolve's_ remaining cooldown is reduced by 50%.
NOTES: This gives her some interesting Draven-like play, but it also helps set up for wall slams.
Q - _Hammer Shock_ - No necessary changes here. Maybe increase to 10% hp as damage, and reduce base damage by at least 20% (does better late, but even or weaker early).
W - _Steadfast Presence_ (Cooldown 16/15/14/13/12)
Passive - Same as before, I think.
Active - **Poppy** twirls her hammer around, dealing physical damage and knocking up all surrounding (300) units for .5 seconds. If cast during _Heroic Charge_, the dash is stopped and all units in the area are instead knocked back in the dash's initial direction 200 units, including her carried target. If her carried target is knocked back into terrain, they take _Heroic Charge's_ damage again and stun as normal.
E - _Heroic Charge_ - **Poppy** dashes to an enemy, dealing physical damage and carrying them along with her for up to 300 units. If they collide with terrain, they are dealt the same damage again and stunned for 1/1.25/1.5/1.75/2 seconds.
R - _Keeper's Verdict_ - Poppy winds up her hammer, channeling for the next few seconds. All enemy units in a cone (135 degrees) in front of her are knocked back 300-750 units (based on channel time) and dealt 150/250/350 damage, which is increased by 0-50% (based on channel time). Units that collide with terrain take the same damage halved.