Do we really want even more quirky shibboleths that can be worn as attire without having to actually learn anything difficult and useful?
I would like some more of those, yes. Tribal bonding is instrumentally useful.
(Of course this is an "all else equal" thing and you want shibboleths that don't turn away outsiders or promote biased thinking or etc etc etc, insert your own caveats. Some of these suggestions seem low-cost and some don't. I'm not persuaded we should adopt any of these in particular, but in principle it seems like a good avenue to explore.)
Is there any rationalist equivalent of "good luck"? I've tried a few variants, such as "work well", "knock them dead", "we're with you" and certain situation-specific phrasings, but haven't found anything that worked generally - though a hearty "may all the gods of Olympus be with you!" can serve. Not a vitally important point, but it would be nice to have something similarly supportive and yet accurate to say.