I may be stating this wrong, but she has a serious case of the certainlyT-s.
its not that any of her kit is powerful on its own, its that shes absolulutely overloaded, like zed, or yasuo.
q-1.good damage skillshot that can
2.pass through if it kills
w-1.infinite mobile wards
2.bonus damage very often, because why not
e- infinitely stacking execute
r-colloquially known as "im not only an ADC, im also a support (first activation) and I can gank my own lane (second actuivation)
passive-bunny rabbit hop
unlike most champs with extra abilities (elise, nid, jayce) all of her abilities go together and doesn't lose anything from using them.
tl;dr
infinite dash, infinite execute, support level synergy with ADC damage, her own support and jg.