while the TL is ok, you don't underestimate the skill of the British Navy, but anyway. There is a problems in North America area, the 1824 election, Jackson success and the social view of him as the man of the people would of still put him as a Nominee in 24, a election which caused Jackson to hate Clay and view him as a traitor. It also caused him to prepare for 4 years for the 28 election.
Edit: also you never dealt with Napoleon's Spanish Ulcer, the government of spain may of like Napoleon, but they could never put down the rebels completely. Even if he won the war, I am sure Spain would of been a problem for many years after.
Next problem, The US Government giving the state of Texas to the Native Population. The only reason we sent them to Oklahoma was because it was considered useless land at the time. Texas as far from considered useless, and it could be said the US had been working since 1812 to bring Texas into the Union. Also even if they allow it, I am sure the Hispanic population of Texas and the Native population, along with settlers would of not gotten along well, and before long the Native American population would of been driven out, unless the US army was going to guard them, which was not going to happen.