I can see Custom Feeds being very useful for onboarding: 
https://cdn.satellite.earth/485d84377ce11354e088832129527d7b11184c82b48f8c219aa18fbbc25a90f0.png

One feed with trending twitter-like posts
One with memes only
One with #introductions etc
Some more Topic focused
...

#nostrdesign #onboarding