My inclination is that tuple foo.bar notation is near exclusively associated with the notion of key/value-paired data. It's used with objects, ports, maps and predominantly key/value blocks. I'd suggest that having the following example work as expected is of greater value than hypothetical irregular dialects:
data: [foo bar bar baz]
data.bar
This is a longstanding frustration and source of confusion (and bugs).
I feel we're unpaving the cowpaths here. We're making it harder (and uglier) to do the most elementary and common things in the hopes that the set-word behaviour is more useful. I don't think tuples should get more complex—that complexity should be passed to functions like SELECT and FIND.