Of the wonders that presumably have to be used for the 4 civs in the first DLC (since it doesn't add any new wonders), only one is really usable for a Modern civ, and that's Oxford. So I think it's very likely that we see Britain in the first DLC. (It's really the only guess that seems extremely likely.)
- Hanging Gardens (Babylon)
- Colossus (Rhodes)
- Pyramid of the Sun (Teotihuacan) [IP]
- Emile Bell (Silla Korea) [IP]
- Ha'amonga'a Maui (Tonga)
- Nalanda (Gupta India)
- Terracotta Army (Qin China)
- Petra (Nabateans)
- Mausoleum Theodoric (Ostrogoths) [IP]
- Shwedagon Zedi Daw (Burma)
- Notre Dame (Medieval France)
- Oxford University (Britain)
You may have missed Dur-Sharrukin (Assyria)
Good list though — this is why I'm convinced Babylon, Assyria, Ostrogoths, Britain, and some form of medieval France are all fairly likely for early DLC.
I don't know if someone being an IP makes a big difference. On the one hand, why would they be an IP if they were planned for early DLC? But on the other hand, what do IPs require aside from a list of cities, which would also be used for a civ?
Pyramid of the Sun is an Antiquity wonder and Aztecs are presumably an Exploration-era civ, so they'll either need a new wonder or some changes.
Both DLC include an "and more", so Ottomans with a wonder is not prohibitive... but it does feel less likely. I also wouldn't be surprised to see Tokpapi or the Blue Mosque in Right to Rule, but that comes after Crossroads, so not sure how that would work. All in all, I'm less confident now that we'll see Ottomans before the first expansion.
All that being said, I don't know how many civs with existing wonders fit the "Crossroads" theme. Babylon and Assyria make plenty of sense... Would they really throw Tonga in a DLC themed "Crossroads of the World"? I think not.
FWIW, I don't think Firaxis is that worried about accurate full pathways much at all. I think they'll get there in time, but the initial roster makes pretty clear it's not their first concern. That said, I do think they're especially interested in adding civs that can draw multiple connections across eras. Think Normans,Goths, Byzantines, HRE — names that aren't quite on tier 1 in terms of overall impact, but can draw lines to several progenitors or successors.