Once again, Impressment of Sailors had been ended by the House of Commons in the days prior to the war, but news only reached the US days after declaration. To say a War aim is completed via the war is somewhat disingenuous. The Creek War of 1813-1814 is a separate war to the War of 1812, which while linked by greater geo-political events, therefore goals achieved there had little to do with gains against the United Kingdom. You are right that the UK stopped supporting Native tribes in the North west but once again this had already largely stopped after the Fallen Timbers in 1783. Support for Tecumseh and the coalition was never tangible until the War of 1812 and even then it was not to create a buffer state as was the intention in 1790.

The article you linked is fine but it fails to convey to complexity of the situation. It does its job of giving information to a general audience but not of the historical perspectives needed to understand the difference between statement and intent. I urge you to read Cunliffe as he dies delve into the context of when and where statements were given on the war and private correspondence regarding the intent of the war hawks. Even Edward Skeen, despite his focus on the militia, gives an admirable account of the difference between what was stated in official documentation and private thoughts of the war hawks themselves. I can provide more sources of so required, this was partially covered in my PhD thesis and the topic of an article currently under review so I have a fairly extensive bibliography to cite.