Livre d'Or

In fact, it's more "lilting" than the languages that are traditionally described as such, because it has intrinsic tone. Apparently proto-IE had it, but I've never come across that feature in any modern day Germanic languages.

Is this why you get "lilt" in both Welsh and an Indian language (don't know which one)? I'd assumed it was independent invention, but if proto-Indo-European had it too, possibly it's the languages on the outside of the Indo-European sphere retaining archaic characteristics (also why Tocharian culture appeared to have similarities to Celtic culture).

lethargic_man described Swedish as looking like a conlang made up by a naive English speaker.

Well, bits of it anyhow...