Jumping in a bit late, but we do have a solution for optimal local routing. It is called SmartZones and is available with free and paid subscriptions. To set it up, look under the network tile in the app.pertino.com console. The short of it is that it allows you to identify a subnet and when devices enter that subnet, they choose the local route over Pertino. Here's the blog from when it was introduced.
Now the longer answer.
In a standard deployment, Pertino uses local name resolution and traffic can be routed locally instead of across the Pertino interface. The reason I say "can be" is because it is really tied to race conditions in the protocol (ie LLMNR in Windows). When you add AD Connect to enable your internal DNS to propagate across Pertino, all traffic ends up being forced across the Pertino interface. Smartzones solves this.
Hope that helps!