I would recommend having Spell Weaving instead of Butcher in your masteries as it helps your allies kill enemies easier. Also, try upgrading Stretching Strike after clearing Gromp. It helps clear the wolves and blue so much easier.

I can see why you would want to use Ranger's Trailblazer, but Stalker's Blade helps a lot with your ganks, and Zac doesn't need the sustain from Ranger's Trailblazer. Chilling Smite can be used mid-air while jumping in, and helps to prevent enemies from escaping, especially later on in the game when trying to pick of a single champion.