I really do like the SBB chimes, and how each one indicates one letter of its 9 letter acronym, and how the relevant one is played depending on the language of the bit you're in. I wish TfW would do something like that (and swap to English first when in England).
That said, my favourite one by far is the German double decker hauled sets that play the first bar of the anthem of the Bundesland they are in as the chime. It's just a lovely quirk. A bit like the Class 175s which play something that is very similar to the first bar of Land of my Fathers but not *quite*.
I do think audio brands are quite important - I did a thread on it a while back - surprises me the railway hasn't come up with a little jingle, or each TOC even. If you listen to a commercial radio station near enough every advert contains one now. I think Nestle might have been first at it with the "do do do de do" thing.
But back properly to the thread, having a jingle does mean you don't need "tuning in" waffle like "Ladies and Gentlemen", so is a good way of avoiding this slightly thorny issue.