Poppy cooldowns are insane.
Q - 8 seconds (small radius, and slows) W - 24 seconds (no damage reduction, garen does it better) E - 14 seconds (extremely situational)
Sunfires cape is pretty damn weak. Grasp doesn't heal enough to compete with Conq's either. Shoves lane with Q, and can't do anything with enemy under tower.
Her ult really doesn't fit in with top lane honestly, and she's too squishy to avoid ganks.