SZ

Yes, but rabbits exist, and Gods and Jabberwockys don't!

But Miranda's Rabbit doesn't exist, as is clear from her piece. I think it is a matter of literary taste (or effectiveness perhaps). Some people find the ridiculousness of the Holy Rabbit works to point out the ridiculousness of the God-talk, whereas you and no doubt others think Jabberwocky works better. Presumably Jabberwocky won't work for those who haven't read the original Jabberwocky story and who have no idea what it is.

The point should surely be that Armstrong-style theists are trying to make real things that even they really concede don't exist, so the appropriate comparison is with other fictional beings that they also concede don't exist.

I really don't think one approach is necessarily more appropriate than another. You could ask which has a more powerful effect, and that is going to depend on the reader (see above).

If God does not need to exist, but questions about God that are important, then why can't I found an ethical system based on the belief in, and ideas of, Sauron? Would Karen Armstrong consider that suitable for general use?

I don't know. But I guess she would probably talk about what communities have found to work over time, the wisdom of ages etc etc.

(Also I'm not sure she would say God does not need to exist. I think these people (though I haven't read much Armstrong I must admit) claim that we should not talk about God existing or indeed *not-existing*.)