Looking for 'best in class' onboarding/implementation content/advice

I'm speaking with a company preparing for an internal workshop on how to improve their onboarding/implementation processes.  Beyond the three articles below, do you know of other great content related to 'best in class' onboarding/implementation?  Would love to hear how others have tackled stepping up their implementation game.  Thank you!

1. User Onboarding that Improves Customer Success and Avoids Churn by Bill Cushard, Head of Training at ServiceRocket 
2. Customer Onboarding is Hard - Avoid this 6 Pitfalls by Amy Clark, Editor of IWantItNow blog.  
3. Onboarding at Gainsight - Making it happen using Gainsight by Allison Pickens, VP CS