I'm reading a BBC novel in which he apparently had the nickname "Snail" but that is probably the opposite of helpful.

You could play around with T.S. as initials, just a thought.

If you are going to go for something different I think you should pick something to suit the incarnation, I have a AU Five named after captain of the English cricket team in 1800s and an AU Eight who's name is an amalgam of Byron references.

But I mostly just do that to amuse myself. Jonh Smith is really fine in most cases.