If we're going on seniority, [[Paris]] should be the character of Greek mythology. At the risk of pouring oil onto the fire, nomenclature like "Paris, France" is an americanism. In both French and British English, we'd write Chester (Cheshire), or Antony (Hauts-de-Seine), giving the county or the departement respectively. For foreign place-names the same style applied: Delhi (India). To British ears, expressions like "Paris, Texas" give the impression of being a single name, that the name isn't "Paris", it actually really is "Paris, Texas". Parentheses would fit in with the house style for other diambiguation pages.
On the wider subject of disamb. in general, I think we're getting a little too bogged down. Part of what makes an encyclopedia useful -- no, fun -- is crosstalk: encountering a dozen interesting article while searching for something, stopping to read them and completely forgetting to look up whatever it was that prompted one to open the book in the first place. That's something we don't have on Wikipedia. There's "random page", but that requires a conscious choice. What we do have is disambiguation pages. They're a way to hop between often very different sections of the encyclopedia. I think we shouldn't bother going back to create pipe links. In brief:
* they're a pain to make * they're a pain to read in raw markup * landing on a disambiguation page adds one click to a reader's stream. big deal. they'll live * and further, it adds to the diversity of what they read
I'd also like to suggest that in cases where one context of an article title is particularly prominent, we use a "disambiguation BLOCK" instead of a page -- that is, open with the standard disambiguation text and links, but run the principal article below on that page.
tarquin