More Russians in the Pacific Northwest.
A different border with Canada.
Canada keeps all of the Great Lakes region.
Different western boundaries for Georgia, the Carolinas, Virginia, Pennsylvania, etc.
Mexico keeps Texas and the Southwest.
California gold rush earlier.
California gold rush later, maybe during the Civil War.
Alaska gold rush earlier.
No Monroe Doctrine.
No Manifest Destiny.
Lincoln, Lee and Davis die early.
Some Alexander-the-Great type unifies the West Indies into a powerful nation ca. 1800.
Cuba a part of the US.
Independent Florida, Texas, California, Vermont, Pacific Northwest.
New York City a separate entity from New York State, which is renamed Albany.
Free blacks given their own state, or independent nation in the West.
The same is done for Indians, Chinese, and maybe others.