I don't think there's anything better than having to use the tools you create to reinforce what is good and what could be better. On an average day, we sign in to MotorsportReg.com sometimes dozens of times to make changes, help organizers or respond to customer inquiries.
For the San Francisco SCCA, we have been helping monitor new registrations to ensure member and transponder numbers are being entered. Although it's a statistically small number of people who fail to enter these numbers, it's immediately obvious that, like the inquiries we respond to, organizers are frequently sending the same emails over and over and over again.
It's perhaps a small lesson but there are two things we've learned from eating our own dog food for a few days. The first is that we need to make it easier to send emails, particularly very similar messages, to individuals. We already have some tickets in our issue tracker for this but being spoiled by SproutIt's Mailroom, which automatically suggests responses to incoming messages, makes us realize we need something similar for outgoing correspondence.
The second is that we could eliminate those emails altogether if organizers could arbitrarily flag which fields in our general profiles are important to them and should be required. This one is trickier since the general contact profile is shared by organizers and is created before they register for an event but we have heard the complaints about missing membership numbers and have experienced it first hand. Now we have an idea of how to fix it.