In this blog post, I will explain how you can show all people by default when you load the page having search result webpart.
I assume in your publishing page you have added search result webpart. Now Edit webpart properties and click Change query
In Build Your Query dialog, select a query dropdown to Local People Results (System) and in Query text add following line:
Now click Test query.
Once you test the query, you will see the result in the right side Search Result Preview panel.
Now click OK and Save the page. You will now able to see all employee directory.