I've mentioned in previous posts that I have some other types of fish in the community tanks with the angelfish. When a pair looks like they'd like to spawn, they are moved to their own honeymoon suite, as in the case with Lindsay Buckingfish and Stevie Fishnick or Robert Redfish and Susan Saranfish.
But when the angels are kept in a community tank, I provide a few hiding areas for some of the smaller fish - just in case they'd like some privacy from the much larger angels.
Corydoras, for example, prefer to sleep during the daylight hours. They become active at night when the angels are asleep. Plecos can also be quite shy, preferring to remain hidden until they are self-assured enough (or large enough) to know they are safe.
In each tank, I have a log where all the fish except the angels can go.
The angels, however, have never shown aggression toward any of my other fish. They will chase them away from eggs but the smaller fish are usually much faster and easily outswim the more sluggish angels.
The biggest challenge when placing other fish with angels is not whether the angels will bother the new fish - but whether the new fish will be tempted to chew on the angels' long, flowing fins. For that reason, I never place barbs with angels. I prefer tetras (except neon or smaller tetras, which can easily be swallowed by a grown angel) and I prefer tetras with long, flowing fins. They are the least likely to be tempted to chew on another's fins.