What are the pitfalls to avoid prior to launch?

There is definitely no list long enough, but as it relates to PH. Rigorously test your product for bugs and errors, establish an onboarding workflow, and have some sort of system for customer support. And another thing is to launch before your launch, so you'll catch some things early and your users will be more forgiving. This is the approach I'm using with www.onlyblog.io. Good luck