Yes there are many creatures in the Astral Realm. Not relating to spirits at all here is a list I know that are in the Astral Plane.
Mermaids
Dragons
Angels
Unicorns
Trolls
Gnomes
Undines
Familiars
You may think I am dumb and there is no such thing as Mermaids or Dragons. But next time you project imagine you are near a Waterfall, Ocean, Lake etc. Then think a mermaid is coming to help you. Then see what that happens. Now Angels are a different story since they are either in Heaven or in a realm or their own. Archangels govern their own realms.
Just try it and see what happens but please don't be rude and post here your stupid, they don't exist. If you are gonna do that don't post at all.
You've actually seen all these yourself? :-o I wouldn't doubt it, it is the astral planes after all.
No, not really. I have read about this and many of my friends that can astral project know as well.