The westernmost Mexican state.
Easy, Balkanized 18th century canada would be 3 colonies (Nova Scotia, Quebec, Newfoundland), the metis in the middle and probably a Columbia colony settled later. The splitting of the provinces happens in 1791, but demographically New Brunswick and Upper Canada are likely to fall to their mother province until at least the 1820s.
- Mexico proper from what were the independence states of Puebla, Mexico, Veracruz, Oaxaca and another one or two I probably forget;
- Yucatan (including Tabasco)
- Central America as per OTL but earlier balkanization could lead to Chiapas remaining part of Guatemala
- New Leon-Tamaulipas as one or two
- New Galicia on what is the OTL state of Zacatecas plus the bits that split from it after independence
- Texas, Coahuilha, New Mexico, Durango, Sinaloa, Louisiana, Upper and Lower California; could be as 8 countries or one.
IIRC the main problem with the Canada and New Spain are
- Newfoundland is tiny; we're talking of only about 20.000 people with low growth. It could be viable but would be extremely poor. Could still be workable, or it could end up being the last northeastern colony. At the time, it has the potential to become a gaelic country, too (but that's a short window)
- On the other extreme, core Mexico is something like 2-3 million people out of New Spain's population of 5-6 millions.
Finally, large parts of Louisiana would probably be out of Louisianese control; Louisiana, Arkansas and the state right above (Missouri iirc) would be the country's's only settled regions early on. Chances are without a powerful US, there would probably be either native states, provinces of whoever is in charge of the pacific north west if a great power sticks around, or independent settler states. Virginia might try to expand some.