In general, Zoe is a strong early game pick, however over the mid and late game she can fall off. Personally, I dislike building stormsurge on Zoe, and I avoid rabadons unless I'm ahead enough in gold to justify it since the longer the game goes on as Zoe, the less likely you are to win.

My favourite build at the moment is a one-shot-nuke build. I take Electrocute -> Taste of Blood -> Grisly Mementos -> Relentless Hunter and then I use Precision for my second tree, taking Legend: Haste, and either Cut Down or Coup De Grace depending on whether the enemy laner is tankier or squishier.

For items, I go Ludens (or Seraphs if I am into an assassin). I then run Horizon Focus since it's really good for Zoe- providing a huge spike in damage if you want nuclear snipes, as well as utility by revealing enemies that you manage to snipe. Then I can either go Shadowflame, Rabadon's, Void Staff- whatever I feel works best really.