I just learned today of a method to have Siri allow you to launch Waze and route you directly to one of your contact entries.
The attached screenshot is the option Siri gives after you say this command:
"Route to home via transit"
This opens the following screen allowing you to choose other routing apps installed on your iOS device. I found that you can say any contact entry with an address and this works.
Also, just to launch Waze with Siri, you can say:
"Launch sounds like Waze"
or
"Launch like Waze"
