Rey, 

Great post!

This is really a great point to look at or understand especially during evangelizing/advocacy practices. To me evangelizing is all about managing or approaching following  items in the context of success, they are: 

1.	High level pre-sales engineering, product marketing, customer matrix to the client or relevant one: helps on-boarding relevant client, product high adoption, increasing number of deals, amount revenue and most importantly time management on checking off the deals. 
2.	How quickly we can get client checked off ? :  supporting high level on doing meetup, presentation (related to product API - code snippets, documentation, tools, ...), various channel mode supporting, and last but not least regular follow-up, etc. 
3.     At the end, make sure or maintain high-level customer satisfaction and relationship management for future engagement  - helps on rolling our scalability, product feedback and growth strategy keys. 

That's it!

Cheers,
Ran